VINCE Cable has unleashed a withering attack on the Liberal Democrats' Coalition partners, branding Tory policies "ugly", "cynical" and "callous".

The Business Secretary, who two years ago attacked City "spivs and gamblers", also suggested they were now back and had "a bridgehead in London and the south east of England and they have got to be stopped".

His comments came hours after Tory backbencher and Downing Street adviser Jo Johnson, brother of London Mayor Boris Johnson, warned against piling taxes onto bankers, saying the Coalition should not be "screwing them for every last penny". Labour said Mr Johnson's comments showed "just how out of touch the Tories are".

In his keynote address, Mr Cable said: "Theresa May once characterised the Tories a decade ago as the nasty party. After a few years trying to be nice and inclusive it has reverted to type.

"We have got dog whistle polit-ics, orchestrated by an Australian Rottweiler (Lynton Crosby), we have got hostility to organised labour, people on benefits and immigrant minorities."

The Secretary of State claimed David Cameron's Conservatives believed that in difficult times "fear trumps hope" and "comp-etence requires callousness".

He declared: "That is not our kind of politics. It is ugly and we will not be dragged down by it. That's why our Liberal Democrat message about fairness is absolutely key."

In the LibDem frontbench's most concerted attempt to date to create clear yellow water between its party and the Tories, Mr Cable insisted the LibDems were not just a nicer version of the Tories but that there were "fundamental differences" about how a stronger economy and jobs were created.

Mr Cable said the LibDems would continue to act against bad practice and announced a formal Government consultation on zero- hour contracts, as well as asking the Low Pay Commission to see if the minimum wage could be raised without affecting jobs.

Later, Mr Cable sought to downplay talk of a rift between himself and Nick Clegg on LibDem economic policy, dismissing claims he had intended to stay away from yesterday's key debate on the economy.

"I was always going to go," he insisted. "Why would I duck out of a big issue like that? I'm always up front and I say what I think, so I turned up and indeed I wanted to support the motion; I wanted to support Nick Clegg," he added.

Responding to the Secretary of State's criticism of the Conserv-atives, Tory backbencher Stewart Jackson said "trashing" the Coalition, which they were a part of made the LibDems "look infan-tile and undermines their pitch" at the next General Election.

He tweeted: "LibDems forget that without Conservative Party they would still be a 'knit your own tofu pressure group' rather than a responsible party of government."

Meantime, Chuka Umunna, Mr Cable's Labour Shadow, said: "While Nick Clegg and the LibDems argue about how much credit to take for their own economic record, 1m young people are unemployed and working people are on average £1500 worse off but people earning millions have been handed a tax cut.

"They are in denial about their role supporting David Cameron's Government."

He added: "The LibDems should admit the truth: they have broken their promises and backed the Tories all the way. Over and over again, they have said one thing and then done another; that's why nobody believes a word Nick Clegg and Vince Cable say."

The British Chambers of Commerce said Mr Cable should engage employers in a "national convers-ation" about pay and productivity but said zero hours contracts were a "niche" issue affecting a relatively small number of workers.

Meantime at a fringe meeting, Mr Cable admitted it was "certainly possible" the Coalition could collapse before the 2015 election and that he could quit. But he stressed: "Obama has demon­strated in recent weeks the danger of parading your red lines in public. I'm not going to do an Obama."

Asked if he still fancied being Chancellor, Mr Cable replied: "I'm not saying yea or nay." He said it was "absolutely not an issue" that he had designs on the leadership.