Around 200,000 two-earner, middle income families will be hammered hard by Gordon Brown's latest stealth taxes, Conservative MP David Willetts has revealed.

The Shadow Works and Pensions Secretary has exposed how thousands of working married couples will lose out under changes in complex tax credit schemes just introduced by Mr Brown.

With all employees - and businesses - already paying more in tax following the weekend rise in National Insurance contributions and while also facing higher council tax bills, Mr Willetts has warned how husbands and wives on middle incomes will no longer benefit as they did before from the working tax credit and the child tax credit.

Addressing a pre-Budget press conference at Conservative Central Office, he said 200,000 families would be hit by changes just made to the tax credit rules - costing them hundreds of pounds a year.

Mr Willetts said, "The new child tax credit adds together the incomes of two partners and then starts withdrawing the credit if their combined income is more than £50,000 a year. This is a shameless breach of the principle of independent taxation. It is also a stealth tax on two earner couples."

Example:

Mr Willetts cited the case of a teacher married to a police officer, with two children, and both earning £30,000 a year:

"Until last week, they got the children's tax credit, worth £529 a year.”

“As from now, their income is added together and it comes to more than the maximum point at which child tax credit tapers out. So now they get nothing. They are £529 a year worse off as a result."

Example:

He also highlighted another example - in which a wife earns £25,000 a year and her husband £30,000:

"Under the old system, they would get £529 children's tax credit. But from now on, they are entitled to the child tax credit, but their combined earnings of £55,000 are in the middle of the income scale where it is tapered out.”

“That means they get £212 this year - £317 less than last.”

"But it's not just a loss compared with last year. The remaining £212 they do get is only half the National Insurance they have got to pay," said Mr Willetts.

Warning that Britain is becoming a nation of means testing and dependency culture wider and deeper than ever before, the Shadow Works and Pensions Secretary said:

"Up to 25 million people could be living in households on means tested benefits by the end of this financial year.”

“Many families will be filling a 12-page form to claim a complicated new means-tested benefit only to end up worse off than they were before. That really is adding insult to injury."