Mexican Formula One driver Sergio Perez announced on Wednesday he is to leave the McLaren team after an unsuccessful season in which his best result was fifth in the Indian Grand Prix.
The 23-year-old, who is likely to be replaced by McLaren's Danish test driver Kevin Magnussen, has garnered just 35 points in his maiden season with them while team-mate Jenson Button has accrued 60 in what has been a hugely disappointing campaign for the stable.
McLaren are without a win or even a podium position this year and are heading towards their worst season in modern times as the team heads to the United States this weekend.
Perez, who earned his moved to McLaren to replace Button's fellow former world champion Lewis Hamilton on the back of impressive performances last season for Sauber with three podium finishes, expressed his gratitude to McLaren and said he was only sorry he had not been able to succeed in his goals for them.
"I will always be a fan of McLaren. In the meanwhile I will be looking at my future to ensure my position in the best possible package to fight for wins," he wrote in his letter announcing his departure and posted on his Twitter account.
Perez, who it was thought would be kept on because of the return next year of the Mexican GP, added he would do his utmost to get the best possible results for McLaren in the remaining two races in America and Brazil.
McLaren team principal Martin Whitmarsh thanked Perez for a statement he described as "kind and gracious", as well as "for being a fine team member during the 2013 Formula One season."