Media playback is unsupported on your device Media caption David Cameron: "We've capped welfare but we need to go further"

Prime Minister David Cameron has ruled out a new tax on expensive properties but vowed "further action to ensure rich people pay their fair share".

He told the BBC's Andrew Marr show new measures would be unveiled before the next election.

His statement comes as Conservative activists gather in Birmingham for the party's conference.

Mr Cameron's decision could put him on a collision course with the Lib Dems, who back such a "mansion tax".

The prime minister also said the UK is considering curbing migration from some European countries and would be prepared to veto a new EU budget to prevent "massive" increases.

Asked about an annual tax on property, he told Andrew Marr: "That is not going to happen."

He said that if people worked hard and saved, invested in a property and paid down their mortgage, he didn't want the UK to "be a country that comes after you every year with a massive great tax, and so that is not going to happen."

Chancellor George Osborne also rejected Lib Dem calls for a mansion tax - and an annual levy on wealth - saying those ideas were not the right way to make sure the rich made a greater contribution.

'Not sensible'

He told Sky News: "I don't think the mansion tax is the right idea because I tell you before the election it'll be sold to you as a mansion tax then after the election a lot of the people in Britain are going to wake up and find their more modest homes have been reclassified as a mansion.

Analysis The conference began with a blizzard of mini announcements. Eye-catching, popular and relatively cheap ideas, on everything from council tax to rail fares to the European Union's budget. The idea is to focus on the cost of living for ordinary people and ram home that the Conservatives get many families are struggling. Both the prime minister and the chancellor said there will be new plans to make sure richer people "pay their fair share". But both also said the idea of a tax on big houses - what Westminster types call a "mansion tax" - isn't a goer. Which begs an obvious question. What is their plan for getting the better off to pay more? The chancellor also said he wasn't keen on a "wealth tax," adding, "in the sense of a tax on your wealth levied annually". So that leaves some wriggle room. Many will now ask in which direction they intend to wriggle.

"Nor do I think it's sensible to have a wealth tax in the sense of a tax on your wealth levied annually.

"But I'm very clear that the rich will have to make a contribution to closing the budget deficit."

In addition to his stance on the mansion tax, Mr Osborne is also understood to have ruled out introducing new council tax bands on high-value homes.

In his Marr interview, Mr Cameron insisted it was "too early to say" whether the government would miss its key target for public sector debt to be falling by 2015, as some experts are predicting.

Council tax freeze

But he said the Conservatives would "level" with the public about the need for another £16bn of spending cuts in 2015-16.

"We have to find these spending reductions and if we want to avoid cuts in things like hospitals and schools - services that we all rely on - we have to look at things like the welfare budget," he said.

But he promised to stand by his promise not to cut universal benefits for pensioners - such as free bus passes and winter fuel payments.

He is also announced a council tax freeze in England for the third year in a row.

And there is to be a cap on how much regulated train fares can go up by - so ticket prices will not rise by more than 1% above the rate of retail-price inflation (RPI).

Liberal Democrat leader Nick Clegg made it clear at his party's conference that he would only sign up to further cuts in the welfare budget if a wealth tax was imposed by the chancellor at the same time.

'We get it'

Questioned about Europe, Mr Cameron confirmed comments by the home secretary in the Sunday Times that a government review was looking at introducing possible controls to limit a new wave of economic migration.

He also suggested the EU should consider having two budgets - one for countries in the eurozone and one for those outside the single currency. Last year he vetoed a treaty to co-ordinate budget policies.

Opening the four-day conference, party chairman Grant Shapps suggested the Conservatives had been too "shy" about trumpeting what they had done to support low and middle-income earners in tough times.

The public were worried about the cost of "paying their bills and filling up their car" and the party had to make clear they were on "the side of every working family".

"People need to know 'they do get it'. But they are not mind readers. We need to go out there and tell them."