New Zealand's Liam Lawson will continue to race for AlphaTauri in place of the injured Daniel Ricciardo at the Singapore Grand Prix.
Ricciardo suffered a broken metacarpal in his left hand in a crash ahead of the Dutch Grand Prix, which also forced him to miss the Italian Grand Prix.
Ricciardo will be present with the team in Singapore for engineering duties.
Red Bull boss Christian Horner said after Monza it is unlikely Ricciardo will return for Singapore or Japan, which hosts a race on Sep. 24, meaning the Qatar Grand Prix on Oct. 8 looks like the most likely return.
Lawson, 21, has acquitted himself well in his two outings with the team and is believed to have an outside shot at a full-time race seat with the team in 2023.
Ricciardo had only returned to F1 two races before his injury, having replaced Nyck de Vries at the Hungarian Grand Prix in July.
The eight-time race winner had been without a race seat for 2023 after being dropped by McLaren, but returned to the wider Red Bull programme as third driver at the start of the year.
Ricciardo is also confident of securing a full year with AlphaTauri next year, as part of his wider goal of returning to Red Bull once Sergio Perez's contract expires at the end of 2024.
Sources have told ESPN Ricciardo is encouraged by plans to make the Red Bull-AlphaTauri partnership stronger next season, which is set to include the sister team taking on a new name and as many parts from the world champions as is allowed under the regulations.
Red Bull effectively has three options for two seats at its junior team, with Ricciardo and Lawson's teammate Yuki Tsunoda enjoying a solid campaign in the other car.