Fire authority employers last night made moves to end the outbreak of unofficial industrial action that has threatened a national strike by firefighters.

The employers wrote to the Fire Brigades Union with a proposal to tackle the row over rest breaks for firemen and women on night shifts.

Meanwhile the union gave an ultimatum to the Greater Manchester fire authority to give a series of undertakings by 4pm today or face strikes.

In the North-East, Durham and Darlington FBU has boycotted a meeting with the fire authority over the way modernisation is being handled.

Brian Boyle, brigade secretary for the FBU in Durham and Darlington, said: "There is a lot of anger among our members.

"I am confident that the membership will support the executive council on their recommendation to take industrial action."

Chief Fire Officer George Herbert said he hoped firefighters would not strike.

"I believe the employers and the FBU overall are fairly close to a resolution on a national basis.

"I would hate to see things happen on a local basis that would in any way either affect that or the modernisation process.

"They are some frustrated and disappointed people in the fire service at the minute.

"This has been going on for quite some time but I believe the relationship between the managers and the firefighters in Durham and Darlington is an honest one.

"We don't always agree but I am determined they will have full possession of the facts before they decide what to do."

Yesterday, more firefighters in Greater Manchester were suspended for refusing to operate anti-terrorist equipment in protest at a hitch to the deal which ended the bitter national strike a year ago.

A total of 47 FBU members were now suspended, raising the prospect of a ballot for industrial action among 2,000 firefighters in the area.

Kevin Brown, the union's Manchester brigade secretary, accused local managers of "jumping the gun" over modernisation changes, adding: "It is unacceptable to seek to prematurely introduce new terms and conditions which have not been agreed."

In Manchester last night union officials met Manchester's chief fire officer Barry Dixon and set the deadline to give a series of undertakings on the working conditions of firefighters.

If it does not, then union representatives will meet in Manchester today to determine the type of industrial action to be called for in a ballot.

Mr Dixon said last night that a fire crew had again been suspended in Salford and more than two-thirds of green watch in Broughton had also been sent home without pay for refusing to use the anti-terror equipment.

He said he could not confirm union reports that a further crew in Stockport had been suspended without pay.

He has written to FBU general secretary Andy Gilchrist demanding he repudiate the current industrial action and he also threatened to begin legal proceedings and seek damages against the union.

In his letter he said: "I can assure you that I do not state this intention lightly.

"However, I cannot allow the current instances of union officials encouraging unofficial industrial action without the support of a ballot to remain unchallenged, placing at risk, as it does, the safety of other colleagues and the public of Greater Manchester.

"I don't want Greater Manchester to be the focus nor indeed the catalyst for the dispute to escalate."

Firefighters across the UK were still answering 999 calls only yesterday in protest at the Manchester suspensions.