Crow vows to lead walkout at TUC if Cameron shows

A jittery Mr Cameron will be meeting TUC general secretary Brendan Barber within the next few days to discuss the Congress invitation.

Rail union RMT announced on Thursday that members had "reacted with horror" at the prospect of the Tory PM addressing delegates at the annual conference in Manchester and threatened to mobilise opposition if his visit was confirmed.

"RMT members up and down the country are leading a grass-roots campaign to get the invitation to David Cameron to address the TUC pulled and we have already made it clear that, if he does pitch up, we will lead a walkout of delegates which will leave his words echoing around an empty hall," said general secretary Bob Crow.

"This Con-Dem government is launching the biggest attack on the trade union movement since Margaret Thatcher set out to break the National Union of Mineworkers and the idea that we should sit there and take a lecture on fiscal fascism from David Cameron is madness."

RMT activists have already won votes calling for the invitation to Mr Cameron to be withdrawn at the north-west and south-west regions of the TUC and at local trade union councils in towns and cities up and down Britain.

The union has said the campaign is gathering serious momentum at the idea of delegates being lectured by a millionaire public schoolboy who has set out to destroy jobs, pensions and the living standards of working people.

Mr Crow added: "The TUC should be a platform for mobilising the co-ordinated fightback against the attacks on jobs, pensions, public services and living standards that are at the heart of this government's programme as it forces working people to pay for the mess created by the bankers.

"There is no way it should be allowed to degenerate into a publicity opportunity for a man whose party is hell-bent on destroying us."

A spokesman for public-sector union PCS said that the union did not categorically oppose Mr Cameron's visit but added that nobody would want to hear what he has to say.

A TUC spokesman said its general council had given overwhelming support for the invitation to the PM to address Congress.

"This was not to endorse his policies but to ensure he addresses the concerns of people at work," he said.

The TUC invitation to Mr Cameron has presented Downing Street with a tricky dilemma.

Aware of a growing storm of anger among delegates and trade union activists, Mr Cameron is believed to be considering a crafty plan B to put his deputy Nick Clegg into the firing line.

The Prime Minister may decide to despatch the obedient Mr Clegg as his messenger boy to address congress and face the protests.