The Tories' campaign against Labour's devolution proposals suffered a setback yesterday when Michael Forsyth, the Secretary of State for Scotland, was ordered to stop making claims that a Scottish parliament would impose a "tartan tax".
Sir Robin Butler, the head of the Civil Service, ruled that the phrase, which is the cornerstone of Mr Forsyth's campaign against a revenue-raising Edinburgh assembly, was "party political" and could no longer be used in official government communiques.
Tartan tax claims have appeared in numerous Scottish Office documents in recent weeks, angering Labour and the Scottish National Party, who have accused Mr Forsyth of using civil servants to peddle Tory propaganda.
Sir Robin's move comes a week after a bitter dispute over a speech by Mr Forsyth in which he used another Tory slogan - devolution converts "new jobs to nae jobs".
George Robertson, the shadow Secretary of State for Scotland, wrote to Sir Robin, the guardian of political neutrality in the Civil Service, asking him to rule whether the phrase "tartan tax" could be used in Scottish Office documents. Labour says a Scottish administration would not raise taxes.
After consultations with Sir Robin, Sir Russell Hillhouse, the permanent under-secretary at the Scottish Office, agreed that the phrase was partisan.
Mr Forsyth remains free, however, to refer to the tartan tax in remarks at government functions, in the Commons, and at Conservative meetings.
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