His admission that the Government helped to drive the economy into the doldrums by not investing in enough construction projects comes as official GDP figures later today are expected to show the UK economy shrinking in the last three months of 2012.
The figures fuel criticism that the Government is not doing enough to kickstart growth and adopt a Plan B for recovery, based on tax cuts and bringing forward more infrastructure investment.
Speaking to the political magazine The House, Clegg said: “If I’m going to be sort of self-critical, there was this reduction in capital spending when we came into the Coalition Government.
“I think we comforted ourselves at the time that it was actually no more than what Alistair Darling spelt out anyway, so in a sense everybody was predicting a significant drop off in capital investment.
“But I think we’ve all realised that you actually need, in order to foster a recovery, to try and mobilise as much public and private capital into infrastructure as possible.
“Wherever we can we’ve got to mobilise more capital investment. The economic evidence is overwhelming. It helps create jobs now – people go on to construction sites. It raises the productive capacity of the economy in the longer run.”
Rachel Reeves, shadow chief secretary to the Treasury, said: “This is the first admission that this Government has made serious mistakes on the economy.
“But the real question is what Nick Clegg’s Government is going to do about it. We have urged ministers to bring forward infrastructure investment and build thousands more homes, but they have refused to listen.”