The fire dispute is over pay and modernisation

It said councils in Scotland, Northern Ireland and Wales all voted to settle the dispute but councillors in London were drafted in to vote against it.

The union has said it will now ballot members over strike action.

Both sides had hoped to reach agreement on Monday in their long-running dispute over pay.

Outstanding issues

They failed to settle a deal on what the union said was a 3.5% rise outstanding since November and a further 4.2% owed since 1 July.

The dispute flared up following problems with the agreement that ended a series of strikes in 2002 and 2003.

A deadlock over "stand-down time" during night shifts was broken during negotiations on Thursday.

That related to whether firefighters should have to undertake training or other duties while waiting for a call-out.

The FBU said employers initially voted to agree all of the outstanding issues including promising to pay salary increases in full.

It is a bad day for the fire service but a disgraceful day for the government and their actions John MacDonald FBU Scottish chair

But it claims that seven Labour councillors from the English Local Government Association (LGA) were drafted in at the last minute to vote against the deal and destroy any chance of settling the long-running dispute.

The FBU's Scottish chairman, John MacDonald, said it was the "most blatant piece of political interference" he had seen in his life.

He said: "Today we came to a meeting where there were 16 on the employers' side and they were going to vote 10-6 to accept the deal.

"John Prescott's department (Local Government and the Regions) drafted in seven Labour LGA councillors who all voted against it, so therefore the deal is now dead.

'Absolutely disgraceful'

"It is absolutely disgraceful. It is a bad day for the fire service but a disgraceful day for the government and their actions."

The Scottish local authority group, Cosla, had also expected the agreement to be rubber stamped.

Head of Cosla, Pat Watters, said: "I thought we had enough on the table to have a resolution today. Unfortunately some of our colleagues on the employers side thought it was too much and that was altered."

He said that he believed an agreement was still possible.

"What we need is good will on both sides. I'm not putting any fault on the trade unions in this particular case. I criticised them in the past but I am not today.

"They held up to their part of the agreement and we have let them down on ours."