Left and right united last night to brand David Cameron and George Osborne liars after they falsely claimed to have halved the budget deficit.

The top Tories launched a poster campaign that attracted ridicule on social media for proclaiming the party had put Britain “on the road to recovery.”

Privileged Prime Minister Mr Cameron told an audience in Halifax that May’s poll would be “the most important election in a generation.” Meanwhile the Chancellor addressed a meeting in Tory target seat Twickenham, where his Lib Dem Cabinet chum Vince Cable is MP.

The new poster boasts of “1.75 million more people in work” and “760,000 more businesses,” despite millions still languishing in part-time and insecure work and bogus self-employment.

But critics were most angered by the claim that Con-Dem austerity has seen “the deficit halved,” which right-wing journalist Fraser Nelson blasted as “misleading.”

The fall in the annual budget deficit from the 2010/11 financial year, which had already begun when the Con-Dem government took office, to the current financial year, has been just 27 per cent.

If the drop were to be calculated using the 2009-10 financial year as the starting point instead, the fall would still be only 36 per cent.

Tory press officers said the ratio of deficit to gross domestic product (GDP) had halved — claiming the word “deficit” could be used to refer to this ratio.

In a blog for the Spectator, Mr Nelson wrote: “(I) don’t dispute that the ratio is widely accepted and more useful to economists, but a deficit/GDP ratio is different to ‘the deficit,’ which is measured in pounds.

“If you want to talk about the ratio, you need to say so — otherwise the sentence is a porkie.”

Andrew Fisher, Left Economics Advisory Panel convenor and author of The Failed Experiment, blasted Mr Osborne for piling misery on workers.

“There’s a cliche that goes: ‘There are good chancellors and those that don’t get out in time’,” he told the Star.

“George Osborne has created a new category — chancellors who start off badly and go downhill from there. Far from eliminating the deficit, Osborne’s austerity programme has succeeded only in driving down living standards and racking up ever higher debt.

“The Tory poster is inadvertently appropriate — a road to a recovery with no homes, no end point in sight and no role for people, either.”

Launching the poster in the Yorkshire Labour marginal, Mr Cameron said: “I say we need to stay on the road to a stronger economy not just because the alternatives are so disastrous — and, frankly, they are disastrous.”

But local MP Linda Riordan told the Star: “This poster will fool no-one in Halifax. The last four years have seen job losses, cuts and service reduction across the town.

“Halifax has quite simply been neglected by this government. What people want is the local A&E saved, new jobs created and investment in public services. Only a Labour government can deliver that for Halifax and other neglected northern towns and cities.”