SECRET Tory plans to cut child benefit and tax credits would rob more than 7 million working-class families, Ed Miliband warned yesterday. 

The Labour leader launched a dossier laying bare the level of cuts needed to meet Tory plans to slash welfare spending by £12 billion.

He said that the analysis proved Prime Minister David Cameron had “put family budgets in the firing line.”

According the dossier, 4.3 million families are likely to lose more than £1,100 every year in child benefit if the Tories retain power. 

Tax credits for poor working families are also set to be slashed by £3.8bn, depriving a one-child family earning just £23,000 of £1,640-a-year.

Overall some 7.5 million families would lose an average of £760 a year, according to the analysis of Tory pledges and independent projections.

Institute for Fiscal Studies experts said yesterday that it was “hard to see” how the Tories could cut £12bn without slashing spending on areas such as child benefit, disability benefit, housing benefit and tax credits.

Speaking in London, Mr Miliband added: “Working families can’t afford another five years of this Tory government.

“And if the Tories deny it, ask yourself why yet again today they haven’t ruled out making changes to tax credits or child benefit?”

The Tories have already withdrawn child benefit from 800,000 families — despite Mr Cameron saying that the cuts were “not a good idea” before the election. 

And the embattled PM refused to rule out further cuts to tax credits when pressed yesterday on Sky News. 

Former Tory leader William Hague told Radio’s 4 Today programme that child benefit was not covered by a commitment not to change tax rates. 

Labour’s document, presented in a brown file stamped “Secret,” opens with a mock-up memo from Chancellor George Osborne to Mr Cameron about the cuts. 

It says: “Please remember, this is not to be disclosed until May 8, best wishes, George.”Labour’s attack could leave the party open to accusations of hypocrisy though.

Shadow chancellor Ed Balls announced plans to freeze child benefit for two years if Labour wins power, saying that the party “must not flinch from tough decisions.”