Daniel Ricciardo is to partner Sebastian Vettel at Red Bull from next season, according to a report in Germany.
Sport Bild online reported that the 24-year-old Toro Rosso pilot has been lined up to place fellow Australian Mark Webber.
Ricciardo will be officially presented as Red Bull's new driver at the Belgian Grand Prix in Spa-Francorchamp next weekend, it was reported.
There has been no confirmation from Red Bull, with motorsport chief Helmut Marko saying: "We will make no announcement until Spa. I cannot say anymore on this."
Lotus driver Kimi Raikkonen and Ferrari's Fernando Alonso had both been linked in media reports with Red Bull.
Raikkonen has also been linked with a switch to Ferrari next year to partner Alonso, although this has been dismissed by the Italian team.
Ricciardo, 24, has been a junior driver with Toro Rosso since 2008 and made his grand prix debut in Britain in 2011.