David Cameron's Tories are just like Ukip – but without the beer, says Vince Cable

Vince Cable today launched the Liberal Democrats’ toughest onslaught yet on the Conservatives’ economic plans, accusing David Cameron and George Osborne of lying to the voters with their promise to wipe out the deficit at the same time as cutting taxes.

The Business Secretary also hit out at his coalition partners’ immigration policies which he claimed had shut the door on skilled foreign workers who could help boost the economy.

Mr Cable continued the leadership’s assault on the Conservatives which has become the dominant theme of the Lib Dem conference in Glasgow. He told delegates: “The Tories are reinventing themselves as Ukip – without the beer.”

He also took a swipe at Conservative promises to cut taxes during the next parliament at the same time as reducing the national deficit.

“The truth is more taxes will be needed. To contribute to deficit reduction and also to address unacceptable inequalities. Any politician who tells you that the next Government can balance the budget and avoid tax increases is lying to you.”

And he appeared to set a “red line” for post-election talks with the Tories on forming a second coalition by insisting he could not support Conservative plans to cut welfare and government spending by £25bn.

“[It] will do great harm to valuable services: to imagine otherwise is fantasy. I will categorically not go along with this,” he said.

Mr Cable challenged the Lib Dems to go out and make a positive case for the benefits of immigration to the UK.

“Our party has a massive responsibility: to be the voice of sanity, seriousness and sense, standing up to the purveyors of panic, prejudice and pessimism.”

He derided David Cameron’s “absurd” promise to cut net migration to tens of thousands by next as “plucked out of the air and totally unenforceable”.

The Business Secretary said: “Overseas students, whose fees subsidise British students and earn £9bn a year for the UK, are discouraged and so go to the US or Australia instead.

“Firms who need specialist skills from Japan, India or the US have to climb piles of red tape, far bigger than anything generated by Eurocrats in Brussels.

“We then train Chinese engineers and insist they go home just when British industry can make good use of them. But, of course, there is always a warm welcome isn’t there for dodgy billionaires willing to make a large party donation for a game of tennis with Boris and Dave.”