George Osborne played down the prospect of swingeing job cuts today as he prepared to unveil the Government’s first £6bn of spending curbs.

The Chancellor said he did not “recognise” figures estimating that 300,000 public sector roles could be lost this year due to efforts to stabilise the record £156bn deficit.

And he insisted the “great majority” of initial reductions in headcount from would be achieved through not filling vacancies, rather than compulsory redundancies.

Mr Osborne and his Lib Dem deputy at the Treasury, David Laws, are due to spell out £6.2bn in savings for this financial year – some £200m more than had previously been promised.

Whitehall travel, IT projects, quangos, outside consultants, and new recruitment to the Civil Service are all expected to be hit.

Speaking on the BBC’s Breakfast programme, the Tory Chancellor said: “What I am saying is that the great majority of the jobs impact in the public sector will be simply by not filling posts.”

Asked about reports yesterday that 300,000 public sector jobs could be lost this year, Mr Osborne said: “I saw that figure in the newspaper and it is not one I have seen anywhere in Government. It is not one that I recognise.”

He stressed that the “front line” of key services such as the NHS would be protected, and said the longer-term effect of cuts would be to boost employment, rather than reduce it.

“The impact of all this will be to increase jobs in the economy because we are allowing businesses to grow,” Mr Osborne said.

He went on: “We have got to understand that the money has run out and so the question for the new Government is: Where do you get the savings?”

The Liberal Democrats signed up to the Conservative plan as part of the coalition deal between the two parties, despite having opposed spending cuts this year during the election campaign.

Deputy Prime Minister Nick Clegg said yesterday that his party accepted the need to act now because of the turmoil in the eurozone caused by the Greek debt crisis.

He said that the coalition would need to hold its nerve as it pushed through the “painful” measures needed to deal with the “great black hole” in the public finances left by Labour.

Asked about the Lib Dem leader’s comments, Mr Osborne said: “Of course there are difficult choices. We have a very very difficult economic situation that we have inherited.

“But I like to be positive. At the end of this process we will have a stronger economy.”

Although most of the money saved will be used to start paying down the deficit, some will be invested in programmes that create jobs and skills, such as apprenticeships, according to Mr Osborne.

However, TUC general secretary Brendan Barber warned that the economy remained “extremely fragile” and that starting cuts this year would jeopardise the recovery.

“Taking any money out of the economy at the moment is dangerous as there is a real risk of a double dip recession, which will only damage the state of the public finances further,” he said.

Reports over the weekend suggested that £513m of savings will come from a “bonfire of the quangos” – with organisations like the Qualifications and Curriculum Development Agency set for the axe.

The Sun reported that Child Trust Funds, a scheme started in 2002 entitling every child to a £250 voucher to be invested on their behalf, are to be scrapped to save £580m a year.

Vince Cable’s Department for Business, Innovation and Skills looks set to be one of the big losers, with reported savings of £900m, while a further £200m could come from university funding.

A freeze on Civil Service recruitment is expected to save another £163m.

It is reported that the Treasury identified further savings from Whitehall’s annual £3bn travel bill – including £125m on taxis, £320m on hotels and £70m on flights.

Further savings could come from the £1bn spent on government advertising and the £580m budget for office furniture.

Consultancy and property costs will also come under attack, and IT projects scaled back or cancelled.

Individual projects to be hit could include an £8m refurbishment grant for the Blackpool Tower agreed in the final days of the Labour government.

The Treasury is also expected to be looking to make savings from the Government’s overseas properties, such as rationalising the four separate offices in the Nigerian capital Abuja occupied by the High Commission, the Border Agency, the Department for International Development and the British Council.