Australian Daniel Ricciardo will leave Renault and race for McLaren in 2021, the British Formula One team have confirmed.
The 30-year-old, winner of seven races for Red Bull, will partner British driver Lando Norris and replaces Spaniard Carlos Sainz who is set to join Ferrari as Sebastian Vettel's replacement.
Ferrari have yet to confirm Sainz's arrival after announcing on Tuesday that Vettel would be leaving after six years at Maranello.
McLaren said Ricciardo had signed a multi-year deal with the former champions, who finished fourth overall last year but have not won a race since 2012.
"Signing Daniel is another step forward in our long-term plan and will bring an exciting new dimension to the team, alongside Lando," said McLaren Racing CEO Zak Brown.
The American paid tribute to Sainz for "the excellent job he has been doing for McLaren in helping our performance recovery plan.
"He is a real team player and we wish him well for his future beyond McLaren," he added.
Renault issued a short statement saying discussions with Ricciardo over a renewal of his contract had not been successful.
They gave no indication of who might replace the popular Australian, although media speculation has suggested double world champion Fernando Alonso could make a comeback with the team that took him to his titles in 2005 and 2006.
The 38-year-old Spaniard last drove for McLaren in Formula One in 2018.
"In our sport, and particularly within the current extraordinary situation, reciprocated confidence, unity and commitment are, more than ever, critical values for a works team," said Renault team boss Cyril Abiteboul.
"I am confident that the 2020 season will allow us to accomplish even more together. Our ambitions and the strategy of Renault DP World F1 Team remain unchanged."
Elsewhere, Ferrari confirmed that Spaniard Carlos Sainz will race for them in 2021 and 2022 as replacement for four times world champion Sebastian Vettel alongside Charles Leclerc.
Sainz, 25, has been at McLaren since last year and Ferrari will be his fourth team after his 2015 debut with Italy-based Toro Rosso. His father and namesake is a two times world rally champion.
"With five seasons already behind him, Carlos has proved to be very talented and has shown that he has the technical ability and the right attributes to make him an ideal fit with our family," said team principal Mattia Binotto.