A Conservative government will "reward" the UK with £7bn worth of tax cuts for enduring the 2008 financial crisis and the subsequent recession.

Prime Minister David Cameron said a Conservative administration would raise the basic rate income tax threshold to £12,500 ($18,763, €16,706) and anyone on the National Minimum Wage (£6.50 per hour for those 21 and over) on 30 hours a week would be lifted out of income tax.

The prime minister also said a Conservative government would raise the threshold for paying the 40p rate of tax to £50,000.

In addition, Cameron promised he would introduce tax-free childcare and recognise marriage in the tax system.

The Tory leader said Chancellor George Osborne will be able to deliver these cuts because the economy has strengthened.

He stressed security is the key theme behind his "rewards" campaign and the past years have been "incredibly hard" for the UK.

"We're at that moment now – what I would call the tax moment, when after years of sacrifice, the British people deserve a reward," Cameron said.

"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."

Cameron also said his government would continue to cut the deficit and promised a Tory administration would crackdown tax evaders, citing the 40 pieces of legislation the coalition government has passed on the issue.

The announcement will be the third in a series of speeches from Cameron as he outlines his party's six election priorities, including the deficit, jobs, taxes, education, housing and retirement, ahead of polling day.

Labour, in response to the speech, claimed the government has "put a privileged few over hard working people".

"Cameron and Nick Clegg should be judged on their record of raising tax on ordinary families while giving millionaires a huge tax cut. They have put a privileged few over hard-working people," said Chris Leslie MP, Labour's shadow chief secretary to the Treasury.

"As the Institute for Fiscal Studies said last week, tax and benefit changes under this government have left households £1,127 a year worse off on average.

"Broken promises on VAT and tax credits have more than outweighed changes to the personal allowance.

"Cameron is now desperately making £7bn of unfunded tax promises. He needs to come clean about whether these would be paid for by another Tory VAT rise, even deeper spending cuts or both."