Former First Minister Arlene Foster said Sinn Féin was an “expert at boycotting” after they walked out of talks at Stormont on Wednesday.
the party pulled out of a meeting to discuss the protocol talks and accused the UK government of “ostracizing” the party by barring its leader Mary Lou McDonald to visit
Sinn Féin said they had been briefed on the details “as a result of last night’s extraordinary turn of events” and said they would not be involved in the discussions.
In a tweet on Wednesday afternoon, Ms Foster recalled the last time the NI executive collapsed in 2017 after the late Sinn Féin deputy first minister Martin McGuinness resigned amid controversy over the failed RHI green energy scheme.
The ex-DUP leader added: “All this hot air about the DUP boycotting the executive looks a bit hypocritical when you’re boycotting talks with the government to fix the problems and get the executive back. But then SF are experts at boycotting (Westminster, NI Exec 2017-2020…..)”
It is understood the SDLP also suggested they would not attend the meeting unless Sinn Féin was involved, with representatives from the Alliance Party saying they would attend.
Arriving for talks at the headquarters of the Northern Ireland Office in Belfast, Alliance MLA Andrew Muir said: “We are here to engage with the Secretary of State and the Foreign Secretary, but it is up to the parties to decide who will do that.”
The Stormont side are due to meet Foreign Secretary James Cleverley and the Secretary of State Chris Heaton-Harris in Belfast.
Negotiations between the UK and the EU on the protocol continue separately.
The sides will also meet Irish Prime Minister Leo Varadkar and Labor leader Sir Keir Starmer on Thursday.
A little more than a week remains until the restoration of the executive power on January 19.
If a new executive is not formed by January 19, the government undertakes the legal responsibility to call early elections to the Assembly by April 13.
In a statement, a Sinn Fein spokesman said: “The progress made on the Protocol this week is welcome and should now add new momentum to the negotiations between the EU and the UK Government to reach a solution.
“Sinn Féin hoped to build on this progress at today’s meeting with the UK Secretary of State and Foreign Secretary.
“However, in an extraordinary turn of events, last night we were told that the British government was shutting down Sinn Fein Wachtharan and party leader Mary Lou McDonald from today’s meeting.
“This is a time for inclusion, dialogue and interaction. This is the time for mature and civil politics. The British government has no room for dishonesty and petulance.
“We have serious work ahead of us in the coming days and weeks. This is an important week and we must make every effort to bring back executive work and work together for all our people.
“We look forward to engaging with the Taoiseach, Leo Varadkar and UK Labor leader Keir Starmer tomorrow.”
A UK Government spokesman said: “This meeting is for Northern Ireland politicians to discuss issues surrounding the Protocol in Northern Ireland with SOSNI and the UK Foreign Secretary.
“The leader of Sinn Fein in the assembly was invited and remains invited. Her involvement is a Sinn Féin matter, but she has not been ruled out.’
Ulster Unionist leader Doug Beattie said Foreign Secretary James Cleverley could not meet Ms MacDonald because he had not yet met the Taoiseach.
Speaking after the round table in Belfast, Mr Beattie said: “It was a shame the SDLP and Sinn Féin weren’t there. It’s good that we all got together and discussed the problems.
“It was really discussed at the meeting. Everything comes down to basic diplomatic norms.
“The Foreign Secretary has not met the Taoiseach (Mr Varadkar) so he was unlikely to meet the leader of the opposition party in Ireland before he meets the Taoiseach.”
Mr Beattie told the meeting that he had sought greater input from local politicians in the Northern Ireland Protocol negotiations.
He said: “We have to be in a position where if they’re going to agree something, we have the ability to say it’s not going to work.
“This is a red flag and I have stated this very firmly to the Foreign Minister.
“He said there would be no ongoing comment on the protocol, no timeline.”