Independent Ulster Unionist peer Lord Maginnis has called for one of Northern Ireland's top civil servants to be "censured" over the removal of portraits of the Queen from Stormont House.
Lord Maginnis blamed Northern Ireland Office (NIO) permanent secretary Sir Jonathan Stephens for the removal of the pictures, which he alleged was endorsed by the then Secretary of State Theresa Villiers.
The peer told the House of Lords last month that the portraits had been taken down after civil servant Lee Hegarty complained under human rights legislation that he was offended by them.
Lord Maginnis yesterday accused Sir Jonathan of "high-handedness" and claimed he should be "censured".
The peer said the removal of the portraits was a serious matter.
"There are questions to be answered over this fiasco, and so far we haven't heard anything coherent from the senior official directly involved," he told the Belfast Telegraph.
"There has been no apology or explanation and that is not good enough." In response to Lord Maginnis' statement, a Government spokeswoman last night said: "The Secretary of State has requested an internal review on this issue which will report in due course."
The review was ordered by Julian Smith last week.
Lord Maginnis said the entire episode raised a series of questions.
"Why did Sir Jonathan do this? What was his motivation? When will the problem be remedied by restoring the portraits to their rightful place at the NIO? Crucially, why was he allowed to act in this manner?"
The unionist peer vowed to keep pressing on the issue.
"We are currently in parliamentary recess but that doesn't mean I intend to let this rest," he said. "Our MPs should be dogged in their search for answers and official accountability.
"This deliberate act deserves a series of parliamentary questions and the appearance of Sir Jonathan before the appropriate Westminster select committee."
The civil servant who lodged the complaint received £10,000 compensation.
Mr Hegarty was subsequently promoted to become secretary and accounting officer of the Parades Commission.
The Equality Commission has said a portrait of the Queen is not considered by it to be a sensitive item for display in a workplace in its guidelines.
However, chief commissioner Michael Wardlow has stressed that the context of how it was displayed was key and could possibly lead to causing offence and disrupting workplace harmony.
Lord Maginnis said that unionist public representatives "would also like to hear from the civil servant who complained and received thousands of pounds in compensation".
The peer added: "Why was he hurt or offended? What prompted his complaint?"
Lord Maginnis said unionists also wanted to know if Mr Hegarty was the only person to have been compensated after complaining about the royal portraits. The DUP has voiced its support for Mr Smith's review and has raised the removal of the portraits with Prime Minister Boris Johnson.
East Belfast MP Gavin Robinson last week said: "It is entirely appropriate that as Her Majesty's Secretary of State for Northern Ireland, he would see no difficulty with portraits of the Queen being displayed here in Belfast.
"We should ensure that displays such as Her Majesty are able to take place, recognising the constitutional position of Northern Ireland.
"In other embassies and Government buildings across the world, there will be pictures of the head of state on display.
"This is appropriate and such a display should therefore be the same for Northern Ireland as part of the United Kingdom."