"David Cameron will make a firm general election pledge to halt next year's planned rise in National Insurance contributions (NICs) for workers and companies, senior Conservative party sources predicted yesterday.
"The move could be the centrepiece of the Tory manifesto. But it would deprive an incoming Cameron government of about £7bn a year of revenue and, to have a credible platform, the party would have to spell out how that would be found.
"Mr Cameron and the shadow Chancellor George Osborne have said that halting the 1 per cent increase in NICs is their top priority but have said they cannot guarantee to do so. It is due to take effect in April 2011."