The Conservative Party is facing more turmoil as some of its top donors have threatened to quit the party over issues such as equal marriage.

David Cameron is also facing calls to break up the Coalition with the Liberal Democrats early, in order to remain leader, following calls from backbenchers.

Some members have threatened to join the UK Independence Party over issues such as equal marriage, and the EU, unless a change in stance is seen from the Prime Minister.

The Sunday Times reports that three of the Tories’ top donors, who have donated millions of pounds combined, have protested the Government on the equal marriage bill, saying it should not have been a priority for the Conservative Party.

In the face of a perceived threat from UKIP, Mr Cameron is being urged to pull out of the Coalition with the Liberal Democrats, at least a year ahead of the next general election in 2015.

Suggesting that Mr Cameron may need to lead a minority government in order to save the party’s seats, one MP told the Times he would have to “choose between insisting on staying in the coalition and keeping his job,”

Lord Kalms, a multi-millionaire former Tory treasurer, said he was “willing to pack my bags”, and join UKIP over the issue of Britain and the EU.

Lord Kalms gave over £700,000 to the party between 2001 and 2012, and recently said UKIP’s policies were “very, very attractive”, and that Nigel Farage was a “top rate guy”.

In a warning to David Cameron, Lord Kalms urged him to stop “sitting on the fence”, and to stop trying “to be all things to all men – that means you are nothing to nobody”.

Mr Cameron has already lost the support of the Conservative Party’s biggest donor, Lord Ashcroft.

This news comes as Nigel Farage has launched an “urgent” fundraising campaign to build on the success of UKIP at the recent local elections.

The Times also reports of a secret plot to trigger a “no confidence” vote in Mr Carmeron, led by Adam Afriyie, a multimillionaire backbencher who has his eyes on the top spot, but whose supporters thought it was not the right time to strike.

Nadine Dorries MP, who recently had the Tory whip reinstated last month, said David Cameron had until the autumn to raise his game.

“We have two years left. Those members who have gone to UKIP won’t be coming back any time soon,” she said.

The divorced Mid-Bedfordshire MP, a staunch equal marriage opponent who was reinstated as a Conservative member last week following her six-month suspension for taking part in I’m a Celebrity, Get Me Out of Here, made a series of critical tweets about the Marriage (Same Sex Couples Bill), which passed its third reading in the Commons, and will head to the House of Lords next week.

Deputy Prime Minister Nick Clegg talked down the idea of the Lib Dems pulling out of the coalition next year, and warned against “destabilising the nation” in the “vague hope of short-term political gain”, in a speech given last week.

Mr Clegg, the MP for Sheffield Hallam, will say that it is “nonsense” to think separating from the Conservatives might “suddenly win back” those people “who have never liked us going into government”, with them.