Brexit Secretary David Davis made another unannounced visit to Northern Ireland yesterday - and met people concerned about leaving the European Union.
His department said he had returned as part of a "fact-finding" mission alongside Secretary of State Karen Bradley and Business Secretary Greg Clark.
It did not say where he visited, only that he met with representatives from the freight industry, cross-border business and community stakeholders "to further explore how the highly-streamlined customs model could address the unique circumstances of Northern Ireland".
The SDLP said it came as no surprise to hear about the visit through news reports.
"It is clear for everyone to see Mr Davis doesn't want to engage with politicians who will put the hard questions to him on his Government's failure to protect the interests of citizens here," the party said.
"Mr Davis would clearly rather sneak about and bury his head in the sand while taking his political lead on the politics of this island from only the DUP.
"Our door is open when the Tory politician decides he actually wants to be responsible and step up to engage at a political level across the political spectrum here."
However, DUP MP Ian Paisley accused the SDLP of sour grapes.
"It was so secret he met with a dozen senior business people and organisations in NI," he tweeted.
"The SDLP feel left out because they have nothing positive to contribute. The Government is going over the heads of the SDLP to the people and the SDLP don't like it."
Sinn Fein MP Orfhlaith Begley said that the proposals being put forward by Mr Davis "on so-called technological solutions on the border are nothing more than rehashed versions of proposals put forward last August which were dismissed by the EU as fantasy and nonsense".
"The clock is ticking and the British Government need to stop wasting time on unworkable notions and deal with the option already on the table for avoiding physical infrastructure at the border through the North remaining in the customs union and single market," she said.
"Rather than sneaking in and out of the North again and meeting behind closed doors, Tory ministers should listen to the views of the people of the North who clearly reject the Tory Brexit and want to remain in the single market and customs union."
Later pictures were issued to the media of Mr Davis meeting with business representatives at Stormont. Businesses represented included the MJM Group, Diageo and NuPrint.
Derry City and Strabane Council was represented, along with the Londonderry Chamber of Commerce.
The Freight Association, WS Dennison, Surefreight and BP McKeefrey also attended the meeting with the ministers.
The Department for Exiting the EU said the visit was part of the 'max fac' working group exploring potential future customs arrangements, focusing on using technology to overcome the difficulties around what will become a land border with the EU as well as maintaining the pledges made by Government of avoiding having additional infrastructure.
The department said in a statement: "The Prime Minister has tasked two working groups from the European Union Exit and Trade (Strategy and Negotiations) sub-committee with exploring further the two possible future customs arrangements the UK Government have set out."
Mrs Bradley said the meeting with stakeholders had been "constructive".
"Throughout our conversations, we focused on how any future arrangements could meet the three clear objectives we have set: to allow trade in goods and services to be as frictionless as possible with the EU; to have an independent trade policy; and, crucially, to uphold the commitments we have made to the people of Northern Ireland," she said.
"That means no hard border between Northern Ireland and Ireland, as well as maintaining the constitutional and economic integrity of the UK.
"And we will keep those at the forefront of our minds as our work continues."
Mr Davis has previously faced criticism for not announcing his visit in advance of his visit to the border in April.
At the time, his department apologised for what it described as a "administrative oversight" in not notifying Sinn Fein MP Mickey Brady of the visit, as is normal procedure.