Daniel Ricciardo hopes to replace Sergio Perez at Red Bull once the Mexican's contract ends, team boss Christian Horner said on Tuesday.

The 34-year-old Australian will be starting his Formula One comeback with Red Bull-owned Alpha Tauri in Hungary this weekend after leaving McLaren last season and serving as Red Bull reserve.

Ricciardo raced for Red Bull Racing from 2014-18, taking seven of his eight wins with the British-based team. Perez, who joined in 2021, has a contract to the end of 2024.

"He (Ricciardo) firmly wants to be pitching for that 2025 Red Bull seat. That's his goal and objective. By going to Alpha Tauri I think he sees that as his best route for stating his case for 2025," Horner told Formula One's F1 Nation podcast.

Ricciardo has replaced under-performing Dutch rookie Nyck de Vries, who failed to score a point this year, at bottom-placed Alpha Tauri with 12 of the season's 22 races remaining.

"At the moment, there's only something in place until the end of the season, so there are no thoughts or expectations beyond that," said Horner.

"We've loaned him to Alpha Tauri to the end of the year. Obviously, our drivers are going to be Max (Verstappen) and Checo (Perez) again next year, but it's always good to have talent in reserve."

Red Bull have dominated the season, winning every race, but Verstappen is a hefty 99 points clear of Perez after winning eight of the 10.

The Mexican's form has led to speculation that he too might not see out the full term of his contract.

Last week's axing of De Vries was seen as particularly harsh since it came before the Dutch driver had a chance to race in his home race at Zandvoort in August, but Horner said delaying the decision made no sense.

He revealed also that the firing came about 11 laps into Ricciardo's impressive tire test for Pirelli after the British Grand Prix.

"That would have meant obviously leaving him in the car until after the summer break," he said. "I think the situation was clear. It was a question of OK, what's the point in waiting?

"If we've got to do something, we might as well get on with it and give Daniel 12 races to see what he's capable of."