Red Bull have agreed a deal to continue using Honda's power unit after the Japanese manufacturer leaves Formula One next year but it depends on a vote to freeze engine development, according to team advisor Helmut Marko.
Honda announced last October that it will end its participation as an engine supplier at the end of the 2021 season.
Red Bull, who finished runners-up to champions Mercedes and have Dutch driver Max Verstappen and Mexican Sergio Perez this season, want to take over the intellectual property of the Honda engine rather than become a customer of another manufacturer.