British Prime Minister David Cameron
BBC
British Prime Minister David Cameron has ruled out a new tax on expensive properties but vows "take 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 decision comes as Conservative activists gather in Birmingham for the party's conference.
Cameron's decision could put him on a collision course with the Lib Dems who back such a "mansion tax".
Another measure set to be announced at the conference is the freezing of council tax in England.
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).
In an interview with the Mail On Sunday, Chancellor George Osborne explained his decision not to create a tax for expensive properties.
He told the newspaper: "Before the election they will call it a mansion tax, but people will wake up the day after the election and discover suddenly their more modest home has been labelled a mansion.
"We don't think people who have worked hard, saved up to buy a home, should be clobbered with a mansion tax."
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.
The coalition has to agree how to cut - or raise - £16bn towards the end of this parliament.
Meanwhile, Cameron has acknowledged that he needs to do more to explain to voters what the party was doing in government.
"You spend a lot of time governing and deciding and you don't spend enough time explaining. I think conference week is a real opportunity to get out there and explain," he told the Sunday Telegraph.
Cameron made clear that he was not ready to concede the political centre ground to Miliband after the Labour leader's party conference speech claiming his was the true "One Nation" party.
"Are the Conservatives deserting the common ground of British politics? Absolutely not," said the Prime Minister.
Cameron also said that he would not stand for "outrageous" attempts to increase the overall EU budget in negotiations on spending for the period 2014 to 2020.