Congressional forecasts published on Tuesday suggest that President George W. Bush is on track to miss his pledge to halve the ballooning US budget deficit within five years.

According to the non-partisan Congressional Budget Office, the deficit will fall from this year's 3.6 per cent of national income - a record $422bn - to 2.1 per cent of GDP in five years' time. The CBO's estimate of the cumulative deficit in the decade to 2014 will be $2,294bn.