The move came as John Prescott, the deputy prime minister, tried to dispel impressions left by the chancellor Gordon Brown that the government would not pay more than 4% if the independent Bain inquiry came up with a credible way of modernising the service.
He also said that the Bain report, not due to be submitted until mid-December, could be speeded up if the FBU agreed to give evidence to the inquiry.
The TUC contact group, consisting of seven general secretaries and TUC general secretary John Monks, could become a conduit for the FBU to give evidence to the inquiry. The idea of the contact group was proposed by Mr Monks to Andy Gilchrist, FBU general secretary, before yesterday's general council meeting.
Mr Monks said: "There is a communication problem. There is plenty of megaphone diplomacy, particularly from the government."
Within the FBU, there are suspicions that Mr Monks is manoeuvring to minimise the strike's impact, but the general council at a meeting yesterday gave unreserved support for the FBU case. Union leaders said the TUC had closed ranks and claimed that attempts by Downing Street to split the unions, by seeking to highlight fears over public safety, had backfired.
The general secretary of the GMB general workers' union, John Edmonds, a member of the eight-member body, said: "It is important the TUC sends a clear signal that the movement is standing shoulder to shoulder with the firefighters".
In a coded form, the TUC also sanctioned unions to spread the disruption by encouraging unions to approach employers to carry out "risk assessments".
The FBU executive will meet in militant mood today to decide what form of emergency cover its members will provide when the first strike starts next week. The FBU has already said it will not respond to normal 999 calls. But it will provide cover during a crisis, such as a terrorist attack or rail crash. The 36 days of strikes begin next Tuesday.
Mr Gilchrist believes there are serious practicalities involved, including contacting strikers and defining incidents that would qualify as exceptions. "They need to stop morally blackmailing professional firefighters and start genuine talks on pay," he said.
In his Commons statement yesterday Mr Prescott repeatedly urged the FBU to think again, saying the strike was indefensible, unnecessary and unjustified. He urged the FBU to participate in the Bain inquiry. One possibilty still being canvassed is for an interim report, although the idea was not welcomed by the Bain inquiry yesterday.
Mr Prescott did little to disguise the scale of the possible crisis. He promised every 999 call would be answered, but admitted that fire cover on strike days would be inadequate.
He told mainly supportive MPs: "The military will not be able to respond to emergency calls as quickly as a normal fire service.
"They will have fewer specialised capabilities and they are unlikely to be familiar with the incident site and local geography. There is no doubt that the risk of loss of life and property will be higher when the FBU members are refusing to work".
Mr Prescott also urged local councils to review plans for bonfire nights and admitted that some sites, such as chemical plants, will need to review safety cover.
He told the unions to "stand by the objective judgment of the health and safety executive and not to use it as an excuse to extend the strikes".