David Cameron was given "strong views" that the cuts will be "socially divisive and economically dangerous" during a meeting in 10 Downing Street.
It was the first official meeting between a Conservative Prime Minister and the leaders of the union movement in 25 years.
TUC general secretary Brendan Barber said afterwards: "The UK is currently in the grips of a bleak midwinter.
"Today we warned the Prime Minister that next year promises to be even bleaker for millions of families and their communities as the spending cuts bite hard and hit jobs and services. We made clear to the Prime Minister our strong view that the spending cuts would both be socially divisive and economically dangerous."
He said he had urged Mr Cameron to do more to raise money from the banks as a sector that had "done the most to take us into the current crisis" and which had received enormous help from government.
The union leaders were offered tea, coffee and mince pies, although one described them as "deficit mince pies" as they were so small.
It is understood Mr Cameron said it would be a good idea for the two sides to meet two or three times a year.