There are fears unemployment could top three million by the end of the year
Gordon Brown has said protecting jobs will be at the top of his agenda over the coming months after "constructive" talks with union leaders.
Getting the economy out of recession was at the heart of a "wide-ranging" discussion with union officials at Mr Brown's Chequers residence, No 10 said.
Unions are concerned that spending cuts will result in widespread redundancies.
Union sources said they warned Mr Brown against a "knee-jerk" response to cuts as a way of reducing the public debt.
The prime minister met 15 trade union leaders for three hours ahead of next week's TUC annual congress in Liverpool.
Downing Street stressed the talks were not "political" despite recent disquiet in the union movement over the extent of spending cuts required to rebalance the nation's finances.
The government says it wants to halve the budget deficit - expected to be £175bn this year - over the next four years but unions say this must not involve mass redundancies.
Despite recent signs of a tentative economic recovery, there are fears that the number of people out of work could top the three million mark by the end of the year.
In a statement, No 10 said the meeting centred on efforts to return the economy to growth as soon as possible.
"It was a constructive and wide-ranging discussion," it said.
"They agreed that pulling the plug on the economy at a time of recession would put the recovery at risk. It was also agreed that jobs will be top of the agenda in the coming months."
"While the prime minister made it clear that there will be tough choices on public spending in future years, he reiterated his strong commitment to the role of public services and manufacturing in Britain's future growth."
The GMB's Paul Kenny told the BBC that union officials had told Mr Brown that "public services have a vital role to play in stimulating the economy and any cut in those services would increase unemployment and stall the recovery".
Before the meeting, Unite leader Derek Simpson said Labour must act decisively on issues such as jobs, pensions and housing if it was not to be beaten at the next election.
The BBC understands that although Mr Brown's performance was discussed at the meeting, his leadership was not raised and neither were the unions' financial links with Labour.
Friday's meeting came at a time of increasingly fraught relations between Labour and the unions.
Unison has threatened not to fund Labour candidates at the next election who support policies which threaten public sector jobs such as further private sector involvement in the NHS.
The level of government spending is set to be a major issue in the build-up to the next election.
Labour says the Tories would reduce spending on essential frontline services if they gained power, choking the economic recovery and increasing unemployment.
The Conservatives, meanwhile, say public spending must be reduced immediately to tackle the excessive level of debt.