David Cameron has launched a savage attack on Gordon Brown in the first prime minister's questions since the Crewe and Nantwich by-election.
Mr Cameron ran with the controversy over fuel tax. "Can he give us one of his trademark U-turns?" he asked.
Mr Brown, clearly prepared for the line of attack, said Mr Cameron's policies were confused.
Mr Cameron accused the prime minister of spewing out statistics. Quoting from the Treasury's own figures, the Tory leader said most car owners would be worse off.
When he attacked Mr Brown for engaging in retrosepctive taxation, the prime minister said there were mentions of the cost to people who already owned such cars in the Treasury documents.
"If a company director got up and read out a statement like that, the authorities would be after him," Mr Cameron replied.
"I don't know why they're all shouting at me," Mr Cameron said to jeering Labour MPs. "It's the prime minister who's given you the worst poll rating since Michael Foot."
Mr Brown went on to point at conflicting policy announcements on green issues from the Tories.
When he then attacked Mr Cameron for cycling to work folowed by cars holding his documents, Mr Cameron said: "It's not my backbenchers telling me to get on my bike."
"We expect these reforms to save 1.3 million tonnes of CO2," Mr Brown continued.
But Mr Cameron read out statements from Labour MPs and green activists showing they thought the reform gave green taxes a bad name.
He then read out a list of anonymous quotes from Labour MPs which lambasted Mr Brown as an electoral liability.
"Just ask the question," the speaker interrupted.
Nick Clegg, leader of the Liberal Democrats, called on Mr Brown to revoke Robert Mugabe's knighthood - the current topic of politics.co.uk's Speakers' Corner.
But the prime minister seemed reluctant to commit to revoking the honour, saying he wanted to concentrate on practical, rather than symbolic, ways of dealing with the Zimbabwean president.
Pushed on the necessity of 42-days pre-charge detention, Mr Brown proclaimed the government's thorough safeguards to secure civil liberties while still taking a firm approach to counter-terrorism.
He also explained the complexity of many terror cases as a reason for the requirement. Like Tony Blair before him, he reeled off a list of names of police groups and leaders who supported the idea.
Boris Johnson stood up - to ecstatic cheers from Tories - for his final moments as an MP. He asked a series of questions, asking Mr Brown to agree with how well the drinking ban on tubes and buses had gone, as well as several other policies he has implemented since taking office. The speaker was forced to interrupt him, but Mr Brown confirmed he agreed with the drinking ban.
Questions began with concerns being raised about the rate of knife crime in the UK, especially in London.
"Knives are unacceptable," Mr Brown said.
He said the penalties for being caught with a knife were rising and supported the greater use of knife arches in tube stations. He proposed prosecutions for 16-year-olds caught with weapons.
There was no PMQs last week due to the parliamentary Whitsun recess.