Ian Paisley has appealed to his North Antrim constituents to keep their faith in him as he apologised in the House of Commons yesterday for breaching parliamentary rules.
In an emotional address, he expressed remorse and said he had made a genuine mistake.
DUP MPs last night maintained a wall of silence on Mr Paisley's failure to declare two luxury holidays paid for by the Sri Lankan government.
Gregory Campbell and Gavin Robinson declined to comment and Sir Jeffrey Donaldson said: "The matter is now in the hands of party officers."
Mr Paisley is facing a 30-day suspension from the House of Commons which will put further pressure on Theresa May, who is reliant on the DUP in key Brexit votes.
Party leader Arlene Foster dodged a question on whether the MP had her full support.
She said Mr Paisley had made a fulsome apology in the Commons and acknowledged his embarrassment, and that the matter was one for the party officer board.
"This was a very serious, a very detailed report that was put forward by the House of Commons," she told the BBC.
"Ian has apologised to the House of Commons. He has apologised to his constituents and he has apologised personally to me in relation to his conduct.
"What happens now is that it is taken to the officers of the party and they will decide what course of action to take in relation to Ian."
Mr Paisley's twin Kyle, a Free Presbyterian minister in England, stood by his brother on social media.
When asked on Twitter about the controversy, Kyle Paisley challenged some of those criticising his brother.
"I have more issues with former terrorists calling for his political blood, who are never happier as when they see people fall; and with political opponents who view a man's fall as a season of opportunity, something to be grasped for one's advantage," he tweeted.
Calls for Mr Paisley to resign have come from across the political spectrum and a successful recall petition would lead to a by-election later this year, something that is widely predicted.
In an address to Parliament yesterday, during which his voice shook with emotion, Mr Paisley appealed to his constituents to retain confidence in him.
A parliamentary watchdog has recommended that he be suspended from the House of Commons for 30 sitting days for failing to register the luxury holidays.
Mr Paisley said it was with "profound personal regret and deep personal embarrassment" that he had to make a statement as he acknowledged he had failed to declare and register the trips.
But he denied he had any "ulterior motive for that genuine mistake" in 2013, adding that he accepted his "total failure".
The Paisley family at home in 1988. From left to right Ian Junior, Cherith, Rhonda, Kyle. Pic Pacemaker
Ian Paisley hurdles a fence during canvassing for 2010 election. Pic Charles McQuillan Pacemaker
Ian Paisley with Donald Trump. The North Antrim MP has supported the US president.
Ian Paisley and Ian jnr eating buns in the campaign trail in March 1982.
Ian Paisley at the Seven Towers Leisure Centre in Ballymena after retaining his seat in the 2015 general election
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Ian Paisley junior left pictured with his father during the Drumcree stand off in 1996. PACEMAKER BELFAST 15/04/98
Ian Paisley MP at a Remembrance Day commemoration in Kenya
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Ian Paisley Jnr with "Justice for the UDR Four " at his Ravenhill office.
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Ian with Arlene Foster after she was made DUP party leader
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Ian Paisley Jr celebrates with his son Matthew and wife Fiona after winning his seat for North Antrim in the UK Parliamentary Elections.
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Ian Paisley Jnr, whose father founded the DUP in 1971, says, 'everybody hates us but we've got the cash' [Photo: Marc McKormick, www.independent.co.uk]
Ian Paisley with his late father. Credit: Stephen Davidson/Pacemaker Press
PACEMAKER BELFAST. Ian Paisley and Ian Junior in Studio. 16/8/94.
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PACEMAKER, BELFAST, 14/1/2011: Ian Paisley Junior pictured at the Adelaide Racer awards at the Ramada hotel
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Paisley with Miss North West 200 Jillian Frew
3/5/2010. PACEMAKER BELFAST. IAN PAISLEY JR POSES FOR THE OFFICIAL ELECTION ARTIST, SIMON ROBERTS WHILST CANVESSING IN THE COUNTRYSIDE OUTSIDE BALLYMENA THIS AFTERNOON. PICTURE CHARLES MCQUILLAN/PACEMAKER.
Pacemaker Press Belfast 22-03-2013: Ian Richard Kyle Paisley, Jr, MP is the Member of Parliament for North Antrim and member of the Northern Ireland Assembly for the Democratic Unionist Party and an author. He is the son of the DUP's founder and former leader, Ian Paisley.
Picture By: Arthur Allison.
Ian Paisley Jr met Amari Wijewardene, the Sri Lankan High Commissioner, in Parliament to discuss a post-Brexit trade deal
PACEMAKER, BELFAST, 11/7/2018: North Antrim MP, Ian Paisley at motorcycle racer William Dunlop's funeral at Garryduff Presbyterian church outside Ballymoney.
Dunlop was killed in a crash during practice for the Skerries 100.
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Ian Paisley speaks to the Irish Times at Stormont Hotel in Belfast, about his father.
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Ian discusses the legacy of his father
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Junior Minister Ian Paisley Junior pictured at photocall at Stormont where ministers were encouraging people to cycle to work.
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PACEMAKER, BELFAST, 8/5/2015:DUP's Ian Paisley celebrates his victory in the North Antrim constituency count in Ballymena .
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A picture posted by Ian Paisley (right) of Arron Banks (second left), Sammy Wilson (second right) and Leave.EU campaigner Andy Wigmore
Pacemaker press 21/4/15 The Democratic Unionist Party MP Ian paisley Junior launches election manifesto at Wrightbus in Co Antrim. Picture Mark Marlow/pacemaker press
Paisley with Melania Trump
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PACEMAKER, BELFAST, 8/5/2015:DUP's Ian Paisley celebrates his victory in the North Antrim constituency count in Ballymena .
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DUP's Ian Paisley celebrates victory in the North Antrim constituency count in Ballymena in the May 2015 General Election. Picture Stephen Davison Pacemaker 8/5/2015.
PACEMAKER BELFAST. Ian Paisley and Ian Jnr.
PACEMAKER, BELFAST, 8/5/2015: DUP's Ian Paisley celebrates his victory in the North Antrim constituency count in Ballymena by singing the National Anthem.
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PACEMAKER, BELFAST, 8/5/2015: Ian Paisley arrives at the North Antrim constituency count in Ballymena with his wife, Fiona.
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Ian Paisley Jr celebrates winning his seat for North Antrim in the UK Parlimentary Elections.
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3/5/2010. PACEMAKER BELFAST. IAN PAISLEY JR AND IAN PAISLEY SR IN HARRYVILLE, BALLYMENA. PICTURE CHARLES MCQUILLAN/PACEMAKER.
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DUP's Ian Paisley Jnr during the Launch of the DUP's General election campaign launch at the Castlereigh Hills Golf in East Belfast on Monday, ahead of the election on the 8th of June.
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PACEMAKER, BELFAST, 8/5/2015:DUP's Ian Paisley celebrates his victory in the North Antrim constituency count in Ballymena .
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Pacemaker Press: 22th December 2017: Ian Paisley Jr pictured with his new and old Passport Picture By: Arthur Allison.
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Pacemaker Press Belfast 31-03-2014: Launch of North-West 200 road races at Titanic Belfast . Pictured at the launch Ian Paisley, Jr. and Arlene Foster, MLA Minister of Enterprise, Trade and Investment.
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Pacemaker Press Belfast 31-03-2014: Launch of North-West 200 road races at Titanic Belfast .Pictured at the launch Ian Paisley, Jr. and Arlene Foster, MLA Minister of Enterprise, Trade and Investment.
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Ian Paisley Jr celebrates winning his seat for North Antrim in the UK Parlimentary Elections.
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The Paisley family at home in 1988. From left to right Ian Junior, Cherith, Rhonda, Kyle. Pic Pacemaker
He offered an unreserved apology "without qualification".
Mr Paisley added: "I say sorry and apologise for the failings that were identified in the Standards Committee report."
He said his constituents have given him "unwavering support" since electing him as MP in 2010, adding: "I hope they will continue to have that confidence in me in the future."
The Commons Standards Committee said Mr Paisley was guilty of "serious misconduct" and his actions "were of a nature to bring the House of Commons into disrepute".
The DUP MP expressed disappointment that he could not persuade the committee about the strength of his arguments and mitigation, including on paid advocacy.
Mr Paisley said he accepted the report but regretted the sanctions.
He continued: "I take my duties as a Member of Parliament seriously.
"I believe I conduct myself with colleagues with integrity, with openness, and that is why I have such remorse about the matter as I believe it goes against the grain of who I am - especially how it is portrayed."
Mr Paisley said he believed in "politics and politicians" who could admit "human frailty, can apologise, can mean it and can move on - because that's what real life is all about".
He stated: "It's often said it's how we respond to these challenges in our lives that defines who and what we are, and defines our character and demonstrates to us where the true source of our personal strength rests. The eighth-century prophet Isaiah said: 'You were angry with me, that anger has turned away, you comfort me.'
"I hope to learn that lesson."
Mr Paisley's potential suspension will start in September if MPs approve it next week.
Members who are suspended from the Commons for more than 10 days are open to a recall petition.
A by-election would be triggered if 10% of Mr Paisley's North Antrim constituency sign that petition.
The suspension will also mean Mrs May will lose one of the 10 DUP MPs propping up her minority government during a period that could see a number of crucial Brexit votes.
The Commons Standards Committee report said the cost of the hospitality during Mr Paisley's Sri Lankan holidays may have been "significantly more" than his £50,000 estimate.
The holidays included business class air travel, accommodation at first-class hotels and more for him and his wider family.
The threshold for registering such hospitality in 2013 was around £660.
In March 2014, Mr Paisley lobbied against a proposed United Nations resolution to investigate human rights abuse allegations aimed at Sri Lanka, with the committee noting that the financial benefits were not declared in his letter to then Prime Minister David Cameron.