The Labour party has sold its headquarters through a corporate vehicle, inviting accusations of hypocrisy over its avoidance of tax through the set-up.
The arrangements caused the Treasury to miss out on about £200,000 in stamp duty, reports said.
The questions came about over the sale of the party's former HQ at 16 Old Queen St earlier this year.
A spokesperson said: 'The sale of 16 Old Queen Street was conducted entirely appropriately and on usual commercial terms, and any suggestion otherwise is not only grossly misleading but absolutely untrue.'
Labour sold the holding company containing the property, 16OQS Ltd, which meant a 0.5% stamp duty tariff instead of a 4% levy. This corresponded to a dent of £210,000 to the Treasury coffers.
Lord Oakeshott of Seagrove Bay, a Treasury spokesperson for the Liberal Democrats said: 'For the governing party to use a device like this is the unacceptable face of tax avoidance.'
Asked whether the same strategy would be employed in the future after the controversy caused by this instance a source said: 'I am not going to talk about the future,' but did confirm that 'there are no plans for further sales' at the moment.
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