Liberal Democrat MPs will be forced to vote for a motion praising David Cameron's performance at last week's EU summit, despite some of their cabinet ministers voicing serious concerns about the Prime Minister's handling of the row.
Parliament will debate a motion from Northern Irish party the DUP congratulating the prime minister for using the veto as "a vital means of defending the national interests of the UK".
The three line whip means Liberal Democrat MPs will be expected to vote in favour of the government - and there was increasing speculation on Tuesday evening about how many could rebel.
At a meeting of Lib Dem MPs and peers this evening energy secretary Chris Huhne warned against isolation and "playing billy no-mates" in the EU.
Earlier on Tuesday, the Cabinet met for the first time since David Cameron's veto of an EU treaty on stabilising the Eurozone.
Sky News claimed that Huhne was "frustrated" at not being consulted over the EU Treaty vote, and was the strongest voice of dissent within Cabinet.
Downing Street revealed that in the Cabinet meeting David Cameron spoke first, followed by chancellor George Osborne, then Nick Clegg.
The deputy prime minister, who didn't turn up for yesterday's Commons debate on the veto, called on the Cabinet to "constructively re-engage with EU at all levels."
The PM's official spokesman said that ministers discussed the EU veto for around 50 minutes of the session, claiming it was a "good conversation," with "different views but a lot of common grounds."
On Monday Nick Clegg insisted the coalition was "here to stay", but there has been speculation about the extent of the gulf within the coalition on Europe since Sunday, when Mr Clegg said it would be "ludicrous" to expect every other member state to form a new set of structures for the "fiscal compact" planned to deal with the single currency crisis.
But the Lib Dem leader, accused of "cowardice" by one Tory MP and mocked as "spineless" by Labour, admitted he and Mr Cameron "clearly do not agree on the outcome" of last week's EU summit.
He renewed his warning that leaving Britain isolated was "potentially a bad thing for jobs, a bad thing for growth and a bad thing for the livelihoods of millions of people in this country".