As Labour's lead slipped in the latest opinion poll, a row broke out over the issue of tactical voting in Thursday's general election.

The row followed calls for tactical voting from Gordon Dean, the Lib Dem candidate in the seat of Norfolk South West. Dean is fighting against former Tory minister Gillian Shephard - where Labour is a close second to the Tories.

In an extraordinary statement, Dean said: "I personally urge every voter in Norfolk to support the candidates of whatever party, Liberal or Labour, most likely to defeat the Conservative candidates in the coming election."

He accused the Tories of being "dishonest, extreme and arrogant".

Lib Dem officials quickly distanced themselves from their candidate's advice and refused to endorse his calls. He had stated "a purely personal view" the party claimed on Saturday.

Angered by the comments, the shadow foreign secretary, Francis Maude, accused his rivals of attempting to re-run the 1997 election.

"People are deeply disillusioned about Labour. They know for the most part a Liberal Democrat vote is a wasted vote and so I think that this won't have any resonance at all. So far as the Liberal Democrats are concerned...they claim to Conservative voters they are anti-Labour, they claim to Labour voters they're anti-Conservative. You can't believe a word they say," he said.

Shephard, who is defending a 2,464 majority gave a cool response, describing Dean's remarks as being "beyond belief".

"Voters locally are capable of making up their own minds. They will not be impressed by the cynicism and arrogance of a candidate who is betraying his own principle and beliefs," she said.

Labour's candidate Anne Hanson welcomed his boost to her campaign.

The latest row came as an ICM poll for Channel 4 News gave Labour its lowest lead of the campaign - 43 per cent. The Conservatives were put at 31 per cent with the Lib Dems on 19 per cent.