Lib Dem David Laws and Labour's Lord Adonis have disagreed over who was to blame about the breakdown of talks about a possible coalition in the wake of the general election.
Mr Laws told the Political and Constitutional Reform Committee, which was taking evidence on the mechanics of coalition building on 14 October 2010, that in the absence of Chancellor Alistair Darling, there was no-one on the Labour team with the authority to negotiate on key economic policies.
But a member of the Labour team, Lord Adonis, dismissed the claim and denied that Labour's team did not want a deal.
"What happened was a political decision on their part to go with the Conservatives. It wasn't anything to do with the composition of the negotiating teams," he said.
Both Mr Laws and Lord Adonis told the committee that the transition to a coalition government following the May general election worked smoothly.
Mr Laws said that negotiating teams from the Conservative and Liberal Democrat parties had had enough time to put a workable solution in place.
"It seemed to me that this was the first coalition formed in this way and the public and the media expectation would be very high that this would happen swiftly," he said.
He added that there was instability in the financial markets, and particularly in Greece, that had been causing concern.
The former Transport Secretary Lord Adonis, who is now head of the Institute for Government think-tank, said the arrangements that were in place prior to the election had "worked in a satisfactory way".
He said events would have proceeded even without a Cabinet Office manual, put together by former Cabinet Secretary Gus O'Donnell, and there was no constitutional issue about what happened in May.
"Events would not have taken a different course," he said.
Mr Laws was a Liberal Democrat member of the team who negotiated a coalition agreement with the Conservative Party, following the 2010 general election result that gave no party an overall majority.
In addition to talks with the Conservatives, informal talks were also held between the Liberal Democrats and the Labour party.
As part of the final coalition agreement, Liberal Democrat leader Nick Clegg was made deputy prime minister, with four other cabinet seats reserved for Lib Dem MPs.