Tory leader David Cameron insisted today that Gordon Brown's "dysfunctional" Government was "collapsing before our eyes".
In rowdy Commons question time exchanges, Mr Cameron taunted the Prime Minister over recent ministerial resignations and urged him to call a General Election.
Mr Brown acknowledged the "great work" done by both Communities Secretary Hazel Blears and Home Secretary Jacqui Smith.
Accused of being "in denial" by Mr Cameron, Mr Brown urged people to "step back" and recognise the last few weeks had been "difficult for every Member on every side of this House".
He said the Government was getting on with the job of taking action to tackle the recession while the Tories would do nothing and had no policies to bring a return to growth.
The clash came minutes after Ms Blears became the fourth minister within 24 hours to announce that she is standing down in advance of a reshuffle.
Labour is also expected to face a drubbing in tomorrow's European and English local elections in the wake of the MPs' expenses scandal.
As turmoil in the Labour ranks dominated the noisy 30-minute session, outgoing Speaker Michael Martin stepped in at one stage to warn that he could suspend the House if people did not quieten down.
The SNP's Mike Weir (Angus) was first into attack pointing to the "pathetic sight of a Cabinet attempting to reshuffle itself" and demanding: "When will you accept you've lost all authority and call an election."
Mr Brown, who arrived in the packed chamber to ironic cheers from the Tory benches, told him: "There is work to be done every day to deal with the recession.
"If we'd taken the advice of the other parties we wouldn't have taken action to nationalise the banks; we wouldn't have taken action to deal with the problems small businesses face; we wouldn't have taken action to deal with the problems people face with unemployment.
"This is the action that needs a Government that is taking action every day."
Mr Cameron said: "This morning the Communities Secretary resigned from the Cabinet. This follows yesterday's announcement that the Children's Minister (Beverley Hughes) is standing down, the Minister for the Cabinet Office (Tom Watson) is leaving and the Home Secretary is resigning.
"Why don't you accept that your ability to command the Cabinet has simply disappeared?"
Mr Brown said: "I think the whole House would want to acknowledge the great work done by both the Home Secretary and Communities Secretary in the Cabinet.
"I think at a time like this the House should come together to acknowledge contributions that have been made in the public interest.
"Under the Home Secretary we have seen crime come down. We have seen neighbourhood policing introduced. We have seen the fight against terrorism stepped up.
"And we have seen better relationships between the police and the community.
"Under the Conservative Government crime doubled and police numbers were cut."
Mr Cameron said: "You are in denial. If these people have done such good work, why are they walking away from their jobs."