NICK Clegg has defended the Coalition's plan to ring-fence certain departmental budgets as Cabinet colleagues press for it to be abandoned.

The Chancellor must find an extra £11.5 billion of cuts for 2015/16 but has promised to protect the budgets for health, schools, overseas aid and defence procurement.

This means other Whitehall departments are facing cuts of between 5% and 10%. It is believed the deadline for secretaries of state submitting plans was yesterday.

One Cabinet insider said that at the start of the parliament when cuts had to be found, ministers were enthusiastic, but now were "having a very tough time of it".

The Deputy Prime Minister said any fresh cuts to the welfare budget would only go ahead if the Conservatives agreed to reform of non-means-tested benefits such as pensioner bus passes and winter fuel allowance.

Given David Cameron has insisted he will protect such benefits for this parliament, means neither is likely.

Mr Clegg said the departmental spending round currently being thrashed out would not be as "gory" as the last one but refused to say how badly non-protected departments would be hit.

Vince Cable, the Liberal Democrat Business Secretary, and Conservative Cabinet ministers such as Defence Secretary Philip Hammond have lobbied for ring-fences to be lifted.

Mr Clegg said: At a difficult time like this, protecting our NHS spending, protecting spending on schools and honouring our international obligations to developing countries was a big decision but it was the right one to take and to stick to."