Shadow chancellor Ed Balls has challenged George Osborne to produce a Plan B for economic recovery.
Mr Balls said disappointing figures revealed last week showed the Government's strategy to revive Britain's economy was faltering.
He was speaking after several leading UK economists told the Observer newspaper of their fears for the coalition's growth plans.
Mr Balls said: "Confidence is down and we are now seeing week by week more evidence the economy is stalling."
He said Labour would cut spending and hike taxes, but slower than the Government.
"The deficit has got to come down, there's no argument about that," said Mr Balls.
"There's no argument there have to be tax rises and some spending cuts. The question is the pace at which you go.
"If you go at a balanced and steady way, the economy recovers, more people are working and paying taxes - that helps get the deficit down. If you go too far and too fast, the danger is it makes it harder."