LIBERAL Democrat leader Nick Clegg has accused his Conservative Coalition colleagues of "beating up on" the poor, as he indicated planned Tory welfare cuts would be a "red line" in future negotiations.

The Deputy Prime Minister said he could not sign up to George Osborne's recently announced freeze on working age benefits. Instead, his party would tax the rich, he said.

His comments are a sign of how difficult any future coalition negotiations could become.

They followed a series of attacks on Conservatives by senior Lib Dems, as the parties highlight the depth of the rift between them just seven months before the next general election.

Among them, Treasury minister Danny Alexander accused the Prime Minister of "trying to score cheap party advantage by making powers for Scotland appear conditional on a particular change for England."

In an interview yesterday Mr Clegg insisted his party would not go into government with a Conservative party committed to moves that would "only penalise (the) working age poor".

Instead, he said, his party would "of course" tax the rich.

Business Secretary Vince Cable also insisted that the Tory welfare plans, announced at the Conservative party conference last week, went "far beyond" what was needed to eliminate the deficit. He added there was "absolutely no way" that the Lib Dems could go along with the Chancellor George Osborne's proposed two-year freeze on working-age benefits. Mr Alexander also announced that the Lib Dems would approve further measures to cut the deficit only if they hit the rich more than the poor.

Earlier, Mr Clegg accused his Conservative colleagues of "beating up on the poor". And he expressed his surprise that Mr Osborne had ruled out tax rises to help reduce the deficit.

Mr Clegg said: "What happened last week ... is the Conservatives said almost with almost undisguised relish that they were not going to ask the wealthiest in society to pay a single penny towards completing the deficit reduction effort.

"Secondly, they were only going to ask the working-age poor to make further sacrifices and that they would savage unprotected budgets, whether it is the police, social services, schools and so on. Those choices - either sticking your head in the sand or beating up on the poor - are not the choices the British people want. They want a balance between a stronger economy and a fairer society and that is what we are offering."