The Prime Minister was accused by the Tories of spearheading an election campaign based on "fear and smear".

The Conservatives deny planning to axe perks for the elderly, including winter fuel payments, free bus passes, free TV licences, free eye tests and free prescriptions.

But Business Secretary Lord Mandelson hit out at the Conservative "hypocrisy" and pointed to a campaign poster featuring a tombstone "designed to frighten elderly people".

Meanwhile, Boris Johnson cast doubt on his own leadership qualities, admitting it would be hard not to "put your foot in it" during a live TV debate.

The Tories also faced accusations of "hypocrisy" from reporters, following the rash of recent front pages targeting Liberal Democrat leader Nick Clegg.

Tory party chairman Eric Pickles said: "The information that was principally used about Mr Clegg we would not have possession (of), it came from his bank accounts and the Conservative Party do not keep the bank details of Mr Clegg."