Tony Blair has lost his authority and his party is in a "state of civil war", Tory leader David Cameron has said.
Mr Cameron says the government must be replaced
He urged the Conservatives to show themselves as a credible alternative government, ready for the next general election whenever it is called.
He said the government was out of control, "running out of steam...ideas, divided from top to bottom" and "the sooner Mr Blair goes, the better".
"This is a government that cannot be renewed, it has to be replaced."
'Faster, deeper and wider' changes
Mr Cameron made the comments as he revelled in his party's best local election results since 1992.
While the Conservatives had had a "good night" at last Thursday's polls, "we should be under no illusions that we still have a long way to go", he said.
Now was not the time to slow down, but to go "faster, deeper and wider" with changes to move the Tories into the north of England and to change attitudes and culture "so we are unmistakably a modern and compassionate Conservative Party", he said.
"We are creating a party that reflects Britain as it is today - we are building a party and a team that is a credible alternative to a government - and I believe the contrast with today's Labour Party could not be clearer," he said.
"They are incompetent, whether it's running our prisons or reshuffling the Cabinet, running out of steam, running out of ideas, divided from top to bottom.
"We were told about a dual premiership - this week we haven't seen dual control, we have seen no control."
He said Mr Blair had "made a great mistake" in pre-announcing his departure "because his authority started to drain away from that moment and now we have this great uncertainty".
"I think the sooner he goes the better, because I can't see how his authority can recover. This is a state of civil war at the highest levels of government and, in any organisation where you're going to have a succession, you need a succession plan.
"There doesn't seem to be one. It's shambolic and the sooner we actually get on with the real contest that's going to be there for people to judge, at the next election, the better."
Mr Cameron said his party's six policy groups on issues such as social justice, public service improvement and tax reform were up and running and getting ready to report.