Honda will confirm tomorrow morning they are to pull out of Formula One unless a buyer can be found by the end of the month.

The announcement is due to be made by Honda Motorsport Corporation in Japan, ending the team's nine-year involvement in the sport.

Honda initially supported BAR with engines from 2000 to 2005 prior to becoming a team in their own right in 2006.

However, exactly seven months after withdrawing their financial support of Super Aguri - leading to that team's demise - Honda themselves are being forced to quit F1.

Earlier this year FIA president Max Mosley made it clear costs in F1 were spiralling out of control, claiming the sport was rapidly becoming "unsustainable."

Mosley has since urged teams to drastically reduce costs in order to survive, but the accelerated global economic downturn has only exacerbated the situation.

Team principal Ross Brawn and chief executive Nick Fry informed the other nine marques of Honda Japan's decision at a meeting in London today of the Formula One Teams' Association (FOTA).

That was followed this evening when the 600 members of staff at the team's headquarters in Brackley, Northamptonshire, were told of the plans.

It is understood that if no buyer is found over the next few weeks, staff will be placed on three months' notice from January 1.

Given the current economic crisis, it is hard to envisage a buyer stepping forward, which would leave just nine teams and 18 cars lining up on the grid at the Australian Grand Prix on March 29.

Honda's decision comes as a bolt out of the blue, just two weeks after they took part in a test in Jerez where they ran the rule over two prospective new drivers in Bruno Senna and Lucas di Grassi.

It now means Jenson Button and Rubens Barrichello are out of a job after nine and 16 years in F1 respectively, unless there is a late reprieve.

With Honda's bombshell certain to send shockwaves throughout the sport, it begs the question as to which other teams might also be on the brink of following in their footsteps.

Mosley is due to hold a meeting of the World Motor Sport Council in Monaco next Friday ahead of the Gala Dinner that will officially see Lewis Hamilton crowned as champion.

It is a meeting certain to be one of the most crucial of his reign.