Fernando Alonso will compete at this year's historic Le Mans 24 Hours race in pursuit of completing motor racing's prestigious 'Triple Crown'.
Alonso, who missed the Monaco Grand Prix last year to take part in the Indianapolis 500, will dovetail his McLaren Formula One commitments to race in a number of sportscar events this season after striking a secondary deal with Toyota.
Le Mans, one leg of the Triple Crown - the others being the Monaco Grand Prix and Indy 500 - takes place the week in between the Canadian and French Grands Prix on June 16 and 17. Britain's Graham Hill is the only driver to have won all three races.
Alonso's McLaren team confirmed the 36-year-old Spaniard, who won the last of his two Formula One championships more than a decade ago, will not miss any of the 21 F1 races this season.
"I've never been shy about my aim of winning motorsport's Triple Crown," Alonso said. "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."
Alonso formally extended his three-year stay with McLaren last October despite a run of miserable results.
The British team's decision to allow Alonso to compete in the World Endurance Championship - effectively adding four additional events on top of his 2018 F1 schedule - is likely to raise a few eyebrows.
"My deal to race in WEC was only made possible through the good understanding and strong relationship I have with McLaren," Alonso added. "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 One 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."
Alonso and McLaren will be desperate for a return to the sharp end of the F1 grid this year. They will be powered by Renault in 2018 after ending their nightmare relationship with Honda.