"Yuki is a very talented driver and has improved a lot this season," team principal Franz Tost said.

"The pace he has shown recently is clear evidence of a steep learning curve, which proves he deserves a seat in F1."

Tost, whose team are fundamentally in existence as part of the Red Bull driver development programme to blood new talent, said: "A driver needs at least three years to fully get to grips with F1, so I'm pleased he's been given the time to show his full potential."

Decisions on the Alpha Tauri driver line-up are made by Red Bull's motorsport adviser Helmut Marko.

Tsunoda said he was grateful for Red Bull's faith, adding: "Having moved to Italy last year, to be closer to the (Alpha Tauri) factory, I really feel part of the team and am glad that I get to carry on racing with them in 2023."

In theory, Tsunoda will be partnered again in 2023 by Frenchman Gasly, who Alpha Tauri have already announced is under contract for next season.

However, Gasly is said to be the number one target for Alpine following the French team's loss of both Fernando Alonso and their reserve driver Oscar Piastri last month.

Alonso preferred to move to Aston Martin when Alpine would not offer the terms he wanted - in particular a two-year contract - and Piastri lost patience with what he saw as Alpine's prevarications and signed for McLaren.

Marko is understood to be prepared to let Gasly go to Alpine if he can find an acceptable alternative, and the leading candidate is said to be Dutchman Nyck de Vries, who has titles in both Formula 2 and Formula E on his CV.

Marko had wanted to sign IndyCar driver Colton Herta, but the 22-year-old American does not have sufficient points under F1's licence-qualifying system to be allowed to race in F1.

Governing body the FIA has indicated that it is not willing to make an exception in Herta's case even though he is a seven-time IndyCar winner and regarded as one of the hottest talents in the US. A number of F1 team principals have backed that stance.

De Vries, who is a Mercedes reserve driver and impressed on a one-off debut for Williams at the Italian Grand Prix after Alex Albon became ill with appendicitis, is also of interest to Alpine.

The Dutchman is one of a number of drivers undergoing an evaluation in a 2021 Alpine at the Hungaroring this week. The test is private and the team have released no information about it, but their protege and Formula 2 driver Jack Doohan - son of MotoGP legend Mick Doohan - is also believed to be taking part.