The Liberal Democrats treat the UK's businesses as an "afterthought" and Nick Clegg "cheated" the country out of reforms aimed at cutting the size of the Commons, Tory chairman Grant Shapps has claimed.
In a strongly-worded attack on his coalition colleagues the senior Conservative accused Mr Clegg's party of not being "as pro-business as you would want them to be" and it was hindering efforts to create jobs.
He was scathing about the Deputy Prime Minister's decision to withdraw support for the coalition's plan to redraw Westminster's constituency boundaries in a tit-for-tat move following the failure to make progress on House of Lords reform.
Mr Shapps told the Express Online website: "Nick Clegg not only cheated his agreement with us, but fundamentally cheated his agreement with the nation by not going through with having fair size constituencies.
"It cannot be right in a democratic society that some people have to have far more people voting in order to elect an MP than other areas."
As the coalition parties spell out their differences ahead of the 2015 general election, Mr Shapps also criticised Mr Clegg for "boasting" about Tory initiatives he had blocked in government.
David Cameron has complained about being "held back" by Mr Clegg's Lib Dems on policy areas including education, welfare reform and immigration.
Mr Clegg, who has made a virtue of saying ''no'' to Conservative schemes, has highlighted a string of proposals he had vetoed - but Mr Shapps said they included a series of potential vote winners.
The Tory chairman said: " I thought it was an extraordinary list as most of them are blooming popular polices he was boasting about stopping."
He also poked fun at another leading Lib Dem, Vince Cable, claiming that the Government's successes in supporting businesses had happened despite the presence of the former Shell economist in the department responsible for backing British firms.
Mr Shapps said : "I think we have done well - now I'm talking tongue in cheek - we have achieved all this and more even with Vince Cable as Business Secretary."
He added: "I'm joking - slightly at least.
"I do think that one of the achievements of the Government has been there are more small businesses than ever before.
"I do think sometimes the Lib Dems are not as pro-business as you would want them to be in order to maximise the amount of jobs which really could be created in this economy.
"I don't want to point any fingers but the instinct from the Lib Dems is still that business is an afterthought or it's a 'nice-to-have'.
"I think it's an absolute driver of families and opportunities of this country.
"I started my own print company and I think there are relatively few Lib Dems who started their own businesses and therefore not quite in the position to understand why it's not 'nice-to-have', it's fundamental for our economic success."
But there was praise for Lib Dem Treasury Chief Secretary Danny Alexander, who Mr Shapps said had "done a very good job".
In a message to wavering voters considering shifting their support from the Tories to Ukip, Mr Shapps warned: "If you want to take control of immigration, if you want to make Britain a great trading nation and outward looking ... you can only do that by voting for it and that means voting Conservative.
"If you vote Ukip, you will make it much more likely that Ed Miliband becomes Prime Minister and you will lose all of these other opportunities."
A senior Lib Dem source said: "Grant Shapps is trying to rewrite history. He should remember that it was the Tories who failed to keep their manifesto promise and coalition agreement to reform the House of Lords, thus denying the public the chance to say who represents them at the ballot box.
"The Tory failure to keep their side of the bargain resulted in us not supporting their boundary reforms."