The British people "deserve a reward" after enduring years of austerity, David Cameron will say today as he attempts to woo voters with his promise of tax cuts after the election.

The Conservatives have already announced £7 billion of tax cuts and the Prime Minister will suggest people should be able to keep more of what they earn to spend on a holiday, clothes for their children or a "nice meal out".

He will warn that Labour and the Liberal Democrats are the "enemies of aspiration" because their plans for the next parliament would involve tax rises.

The Prime Minister will point to Treasury analysis showing someone who had been a basic rate taxpayer since 2010 will have paid £8,000 less in income tax by 2020 under Tory plans.

In his third speech this year outlining key manifesto themes the Prime Minister will say that tax cuts are a reward for "years of sacrifice".

The Tories have set out plans to raise the personal allowance to £12,500 by 2020 and to take hundreds of thousands of people out of the 40p band by raising it to £50,000 over the same timescale.

The Conservatives said the analysis by the Treasury showed the benefits for someone earning between £12,500, the personal allowance threshold planned by 2020, and £41,500, the lowest rate at which the 40p band was set between 2010 and 2020, would be at least £8,000 over the decade.

Mr Cameron will say: "I sometimes get asked: why do I believe in tax cuts so much? It's simple, because I trust people more than I do politicians.

"I think people know how to spend their money better than those in Westminster do. I believe that if people have worked hard and earned their own money, they should be able to spend it on a holiday, or a nice meal out, or some new clothes for their children - and that it shouldn't be thrown up the wall to satisfy the latest gimmick dreamed up in Whitehall.

"This is the right thing to do: it's your money, not the Government's, and so you should keep it."

The Tories have committed to eliminating the deficit over the coming years through spending cuts and a squeeze on welfare rather than tax rises.

The Prime Minister will point out that alongside the austerity measures so far, the Government had been able to spend £10 billion on income tax cuts - claiming credit for the policy of raising the personal allowance that the Liberal Democrats have championed as their own.

Mr Cameron will say that the country is at "the tax moment" where "after years of sacrifice, the British people deserve a reward".

He will say: "Let me put it like this: in the wake of Labour's Great Recession, these past few years have been incredibly hard for this country.

"But after some dark times, we are coming out the other side. And as we do, I'm clear - the people whose hard work and personal sacrifices have got us through these difficult times should come first. So it's right that where we can ensure people keep more of their own hard-earned money, we should."

Both Labour and the Liberal Democrats have said that the effort to eliminate the deficit in the next parliament should involve extra taxes on the wealthy.

But the Tory leader will insist that his approach is the right one: "Before us lie what I would call the enemies of aspiration - and they are the Labour Party and the Liberal Democrat Party."