Media playback is unsupported on your device Media caption Lord Tebbit: Cameron "has got badly off track"

Former Conservative chairman Lord Tebbit has called on the party to set a date for an EU referendum as part of efforts to win back voters from the UK Independence Party.

UKIP made gains in local elections as the Tories lost control of 10 councils.

Lord Tebbit also said Tory policy was "badly off track" and needed a rethink.

Home Secretary Theresa May insisted Tories could win back voters but rejected calls to bring forward a referendum to counter the UKIP threat.

Prime Minister David Cameron had made it clear a referendum on the UK's membership of the EU would take place early in the next parliament, she said.

However, the public needed "greater certainty" that a referendum would happen, she added.

UKIP, which campaigns for the UK to leave the EU, averaged 25% of the vote in the wards where it was standing in Thursday's elections and won more than 140 seats.

Most people in the country agree we are being mucked around by our friends in Brussels... most people think that immigration is too high... most think that welfare has got out of kilter Lord Tebbit

In response to Mrs May's comments, UKIP leader Nigel Farage said: "She is asking us to trust the PM on a matter of a European referendum.

"He has a remarkably bad track record of keeping his word on this particular matter."

In opposition, Mr Cameron promised to hold a referendum on the Lisbon Treaty amending the EU constitution but, once in power, said he was unable to do so because it had already been ratified.

'Psychological barrier'

In a BBC interview, Lord Tebbit, an ally of former Prime Minister Margaret Thatcher, urged Mr Cameron to immediately put legislation in place to allow for a referendum and set a date for it.

That, he said, would present a real challenge to Labour leader Ed Miliband to make it known where he stood.

He also accused Mr Cameron of going "badly off track" by veering too close to the Liberal Democrats.

He said too many people were beginning to prefer what UKIP was offering - which he called the "politics of the common ground".

"Most people in the country agree we are being mucked around by our friends in Brussels... most people think that immigration is too high... most think that welfare has got out of kilter."

Politics seems to be something that's done to them, not for them Gerrard Batten, UKIP MEP

He urged Mr Cameron to look at UKIP's policies and consider which were "really Conservative policies that would be attractive to the party and its traditional voters".

"And there's quite a lot of them," he added.

Sarah Newton, the Conservative Party deputy chairman, and senior Tory David Davis also called for legislation for a referendum to be brought forward.

Mr Davis, who lost the contest to become Tory leader to David Cameron in 2005, said UKIP's policies on law and order, immigration, taxation, foreign affairs, and Europe "mimic a simplified 1980s Tory manifesto".

He called for more conventional Tory policies and urged Mr Cameron to deal with immigration "fears", take steps to cut taxes and stop giving the impression Tories were "privileged and out of touch".

BBC political correspondent Iain Watson said most Tories would not expect a referendum this side of the election but would want draft legislation in place.

Gerrard Batten, UKIP MEP for London, said UKIP's performance on Thursday had "broken the psychological barrier with the electorate", as voters now believed a vote for UKIP could count in the first-past-the-post system.

He said for a long time voters had thought politics was "something that's done to them, not for them", but now they have "seen something different that they can believe in".

The party's new councillors would represent ordinary people without being bound by a party machine, he added.

He said he expected Mr Cameron would continue to try to "con" voters over an EU referendum.