Tony Blair, Michael Howard and Charles Kennedy engaged in heated exchanges over the choice facing voters in the general election.

In their Commons clash, the Conservative leader raised questions about whether the prime minister could be trusted to keep his promises.

But Blair warned the electorate that their jobs and mortgages were at risk if they voted Tory.

The Liberal Democrat leader, meanwhile, said that more should be done to help pensioners and students.

Honesty

The high octane exchanges - the last direct clash between the party leaders before May 5 - prompted cheers and jeers from all sides of the house.

Howard began by saying that Labour had broken a promise not to raise National Insurance after the election.

But Blair said there had been "specific promises" only on basic and top rate tax levels.

He conceded that National Insurance had gone up to pay for extra NHS investment.

"We are proud of the investment in the National Health Service," he said. "Under this government at least, the National Health Service is safe."

Top-up fees

Howard returned to the despatch box to remind MPs that Labour had also broken pledges on top-up fees.

The prime minister "couldn't bring himself to say a word in defence of those broken promises", the Tory chief added.

Blair said Labour was delivering extra investment, while Howard had introduced the poll tax, overseen rising unemployment and cut the numbers of police when he was in government.

The Tory leader, however, mocked Blair's popularity - asking how many Labour MPs would use the prime minister's photograph on their election addresses.

Suggesting few Labour MPs would use the image, Howard said: "Doesn't that tell you all you need to know about what they really think of him?"

Blair said Labour would be using Howard's photo instead to remind the electorate of his record.

And he added that the election would be a choice between Tory cuts and a Labour government that had delivered economic stability and higher investment in schools and hospitals.

Key clash

In the final set of exchanges between the two party leaders, both were under pressure to end the parliament on a high note.

Howard said Labour's record in government was a failure.

"Taxes up, crime up, immigration up, waiting times up, MRSA up, truancy up," he said as his backbenchers joined in.

"And let's have a look at what has gone down. Take-home pay down, pensions down, productivity growth down, manufacturing employment down, detection rates down."

He added: "Isn't there now a clear choice at this election? Rewarding this prime minister for eight years of broken promises or choosing a government that will take action on the things that matter to hard working Britons."

The prime minister agreed there was a "very, very clear" choice for voters.

"People remember the years before 1997," he said

"People remember the people who lost their homes in the recession, that lost their jobs in the recession, that used to end up with mortgages they could not afford."

He added: "And what we will remind them of between now and polling day is what they have now and what is therefore at risk.

"What they have now is the economic stability and the investment in public services and the action on crime. So the choice is indeed very clear."

Blair said the clock could be "turned back" under a Conservative administration.

"Yes, it is a big choice and I can't wait till the public make it," he concluded.

Fairness

In later exchanges, Charles Kennedy challenged Blair on two of the Liberal Democrats' key campaign themes: pensions and student fees.

The Lib Dem leader asked the prime minister why his government has not tackled the gap between men and women's pensions entitlements.

Kennedy wants to introduce a "citizen's pension" based on residency rather than national insurance contributions, which women often lack because of family responsibilities.

"After eight years of this Labour government the prime minister will recognise that most women in this country still do not receive a full state pensions in their own right," he said.

"Surely women should receive a pension as of right?" Kennedy added.

"After eight years why hasn't the prime minister put that right?"

Blair pointed out that under his premiership the "living stands of pensioners have risen considerably", with more help going to older women.

He said the winter fuel allowance, free TV licenses, pensions credit and help with council tax had all been introduced under Labour, as well as increases in the state pension.

"I think this government has got a record on pensions of which we can be very proud," the prime minister said.

"Of course there is more to do and we will do it if elected."

Students

Kennedy then asked why students are leaving university with "thousands pounds of debt wrapped round their necks" despite Labour promises not to introduce top-up or tuition fees.

"Why should any of us believe any of the promises he makes at the next general election?" he asked Blair.

The prime minister replied that under new plans "there will be no fees paid at all while students go through university" as well as interest free loans.

"We have got to get more money into our university system," he added, arguing that Lib Dem plans to scrap fees through higher top rate taxes do not add up.

Blair, Howard and Kennedy are understood to have agreed to appear in the same edition of the BBC's Question Time, but Wednesday's clash could be the closest they come to an actual election debate.