Bill Morris, general secretary of the Transport and General Workers Union (TGWU), said Labour was creating a "dangerous divide" between the party and its natural supporters.

The Conservatives would have applied the same old Conservative solutions - to imply otherwise is entirely misleading

John Reid Labour Chairman

The comparison with the Tories has been dismissed by Labour Chairman John Reid, who said nobody should have any problem discerning the differences between the two parties.

Mr Morris, a Labour loyalist, is the latest union leader to speak out against the government's policies, especially its hardline treatment of the firefighters.

He told BBC Radio 4's Today programme that Labour was acting as the "pathfinder for future Tory policies" on issues such as Foundation Hospitals and university top-up fees.

Clear blue water

Mr Morris was speaking two days after joining thousands of trade unionists in a march and rally in central London on Saturday in support of the Fire Brigades Union.

In an article in the latest edition of his union's journal the T&G Record, Mr Morris said a philosophical difference between the two main political parties had taken Labour to power in 1997.

I doubt the public will be keen to support this new Labour approach of excellence for the few and a safety net for the many

Bill Morris

"When the Tories were in power they used to boast of the clear blue water between them and Labour, but since the Queen's speech it is difficult to find the line between Labour and the Tories," he said.

"The dividing line between our parties seems to be blurred if not erased altogether.

"I doubt the public will be keen to support this new Labour approach of excellence for the few and a safety net for the many."

'Disgraceful'

Mr Morris warned the party against pursuing a market economy in public services.

"My fear is that by pursuing policies like foundation hospitals, university top-up fees and describing decent trade unionists as wreckers and dinosaurs, Labour is creating a dangerous divide between the party and its natural supporters," he said.

Firefighters' pay talks are set to resume this week

He told Radio 4's Today programme that the dividing line between the parties had to be restored.

But Labour Chairman Mr Reid said the distinction was clear and Labour's policies were based on an entirely different set of values.

He said the Tories would not, for example, have introduced a minimum wage or boosted public service investment.

Dr Reid added: "The truth is that the Conservatives would have applied the same old Conservative solutions - cuts in public services, mass unemployment and further restriction of opportunity.

"To imply otherwise is entirely misleading."

The FBU's general secretary Andy Gilchrist told the 9,000-strong rally on Saturday that the way the government had intervened in the national fire dispute was "shambolic shameful and incompetent".

He said ministers' interventions to block a 16% offer that was tabled the night before the recent eight-day strike began were "disgraceful".

The government vetoed the deal because, it said, anything over 4% would have to be paid for through modernisation.

Further exploratory talks are expected to be held this week at the conciliation service Acas in a bid to break the deadlocked firefighters' pay dispute.

The FBU executive will meet on Tuesday and Wednesday to review any progress been made at the talks.

The findings of the review of the fire service by the team chaired by Sir George Bain are due to be published on 16 December - the same day the union is threatening to go ahead with a second eight-day strike.

Further industrial action is planned for January, February and March of next year.