ULSTER Unionist leader Robin Swann told MPs yesterday he believed that Arlene Foster handed Michelle O'Neill a draft power-sharing agreement days before the Stormont talks collapsed.
The DUP leader and Sinn Féin vice president disagree on whether a draft deal existed before recent talks broke down.
Mrs O'Neill has claimed Mrs Foster gave it to her in person on February 9.
Mrs Foster has insisted no agreement was ever reached.
However, Mr Swann told the Northern Ireland Affairs Committee: "I think I am pretty sure in my head it was an agreement between two parties."
Mr Swan also rebuffed a suggestion that his party could merge with the DUP.
He said unionism in Northern Ireland could not be seen as a homogenous group and that many differences remained between the two parties.
He was responding to a question from Labour MP Kate Hoey, who asked if the UUP and DUP would consider joining forces as one party.
"A merger with the DUP? No. Unionism in Northern Ireland has its different outlooks. To see unionism as one homogenous group in Northern Ireland doesn't work," Mr Swann said.
He said that both parties have different outlooks on a number of issues, including social issues such as abortion and same-sex marriage.
Mr Swann said the issues of abortion and same-sex marriage were a "matter of conscience, not something that should be dictated".
"There are quite a number of differences between us", he said.
Meanwhile, Green Party leader Steven Agnew told the committee that he was embarrassed to still receive full pay more than a year after the collapse of power-sharing in the region.
"I think we are at a point where it should be (reduced). I think it is untenable," the MLA said.
"I believe (salaries should be cut). Not for a second because MLAs aren't working hard, but we are not performing one of our key functions which is to legislate."
TUV leader Jim Allister and Mr Swann agreed with the Green Party leader.
Mr Allister said he has already instructed Stormont to no longer pay him part of his salary. He told committee members that following his instruction he is no longer receiving travel allowance, which amounts to around £500 per month.
Mr Agnew also told the committee he believes there should be a review of the Good Friday Agreement (GFA) through a Citizens Assembly.
"We are 20 years on from GFA. Politicians took power and guarded it jealously. We have to go back to the people and ask their consent," he said.
