Fernando Alonso will join the works Toyota team at Le Mans and additional selected rounds of the World Endurance Championship this year.
Alonso's inclusion in the Japanese manufacturer's line-up this year at Le Mans was widely expected following the two-time world champion's proclaimed ambition to tackle motor racing's Triple Crown.
The Spaniard, who enjoyed a day of testing with Toyota in Bahrain late last year and made his sportscar debut at Daytona last weekend, will also race in the WEC although he will not take part in the October round in Fuji as the race clashes with the US Grand Prix in Austin.
Unfortunately for British fans, Alonso's arrival at Toyota will be to the detriment of Anthony Davidson.
The manufacturer's LMP1 squad will include usual drivers, Mike Conway, Kamui Kobayashi and José Maria Lopez in the #7 car, while Alonso will be paired with Sébatien Buemi and Kazuki Nakajima in the sister #8 car.
Alonso's commitment to McLaren will take precedence over his deal with Toyota.
"Like Fernando, at McLaren we’re racers at heart, and our team is built on a brave heritage of competing and succeeding in different forms of the sport," McLaren's Zak Brown said in a statement on Tuesday.
"Equally important is the confidence that nothing detracts from our number one goal of Formula 1. After proper evaluation, we are satisfied that this campaign does not do that, and that McLaren’s best interests prevail."
Alonso reiterated his Triple Crown ambitions and his natural propensity to race out of his comfort zone.
"I’ve never been shy about my aim of winning motorsport’s ‘Triple Crown’ – the Monaco Grand Prix, the Indy 500, and the 24 Hours of Le Mans. We tried for Indy last year, came close, but just missed out.
"This year, I have the chance thanks to McLaren to race for the win at Le Mans. It is a big challenge – much can go wrong – but I am ready, prepared and looking forward to the fight.
"My deal to race in WEC was only made possible through the good understanding and strong relationship I have with McLaren, and I’m very happy that they listened and understood what this means to me.
"In no way will this challenge take away from my main target of Formula 1 with McLaren. In 2018, my aim is to be competitive at every grand prix, and I feel sure that we are closer to achieving that."
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