http://news. bbc.co.uk/ sport2/hi/ motorsport/ formula_one/ 7860648.stm
McLaren & Ferrari in united frontFormer bitter rivals McLaren and Ferrari are now "working extremely closely together" as teams seek to show Formula One's rulers a united front.
McLaren boss Ron Dennis confirmed their growing off-track ties on Thursday and said the result has proved "profound".
Ferrari spokesman Luca Colajanni also spent the day at McLaren's Woking factory meeting Dennis and other staff.
"If you had told me a year ago that I would be doing this I would not have believed you," he said.
Reigning constructors champions Ferrari and McLaren have a chequered recent history.
The English team was fined a record $100m (£70m) in 2007 and stripped of all their constructors' points for their involvement in a spying controversy over leaked Ferrari technical data in their possession.
Ferrari also started legal action against their rivals, with Dennis and other executives questioned by Italian police, though the action was later dropped after a McLaren apology.
But the team's top personnel, and the wider climate in which they operate, has since changed significantly.
With the urgent need for cost cutting becoming apparent, the Formula One Teams Association (Fota) was set up in July to represent teams in talks with with the governing International Automobile Federation (FIA) and commercial supremo Bernie Ecclestone.
Jean Todt also handed over as Ferrari boss to Stefano Domenicali while Dennis is due to step down as McLaren principal on 1 March to make way for Martin Whitmarsh.
Fota are headed by Ferrari president Luca di Montezemolo, who has criticised Ecclestone's running of the sport.
With FIA president Max Mosley stressing that he is keen to see a significant shake-up in the sport towards cheaper operating costs and, potentially, more standardised engines, Fota is determined to provide a strong voice for the interests of all F1 teams.
While Fota have agreed significant savings with the FIA for this season and beyond, they want to secure a greater share of the sport's commercial revenues than the 50% they currently receive.
Montezemolo recently described Dennis as "a first-class person from a first-class team" and said the sport needed great competition on the track and great unity off it.
And Dennis, who has said he will soon devote more of his time to Fota activities, told the official F1 website: "The result of our co-operation, supported by all the other teams, has already been profound.
"Fota has already achieved great things, and it will achieve even greater things in the weeks, months and years to come.
"We're not complacent; we're not reluctant to embrace radical change; we're not hidebound by on-track rivalries.
"Working together for the good of the future of F1, we'll continue to devise powerful strategies and innovations intended to improve our sport so as to make it more affordable, more environmentally friendly and more appealing to spectators and TV viewers."