Tories in four-fifths of the 100 councils contacted had either voted for Labour motions condemning the tax or had failed to oppose them, Ms Harman said.
The research found that an anti-VAT motion was passed unanimously by Tory-controlled Enfield, north London, which includes the Southgate seat of Michael Portillo, Chief Secretary to the Treasury. On Ribble Valley council, Lancashire, all 25 Conservatives voted for a similar motion tabled by the council leader. On Gillingham council, Kent, all 16 Tories rebelled.
The tax is due to take effect in April, one month before some councils face elections.
Stephen Dorrell, Financial Secretary, accused Ms Harman during Treasury questions in the Commons yesterday of 'scraping the barrel' by suggesting that tax policies should be determined by individual local councillors.
Ms Harman said later: 'The Government has lost its majority in the Commons and cannot reconstruct it against this tidal wave of opposition. If the Government doesn't back down in the November Budget, Labour will force a vote on the issue before April.'
Labour distanced itself last night from a leaked document containing plans to revive London, paid for by new taxes. Some of the proposals, including an elected Greater London Authority, half of whom would be women, are expected to become party policy before next year's London borough elections. But a source said proposals for raising revenue by taxing tourism, large cars and airports had been rejected by Labour's policy committee.Reuse content