McLaren are considering a shock engine partnership with Red Bull.

The PA news agency has been told that McLaren chief executive Zak Brown visited Red Bull Powertrains – the engine division of the team which last season dominated Formula One – earlier this month to explore a potential deal.

A Red Bull spokesperson confirmed to PA on Wednesday that Brown has been at their factory.

Red Bull’s engines are currently supplied by Honda, but the world champions will make their own power units from 2026 to coincide with a major overhaul of the sport’s regulations.

It was recently announced that American car marker Ford would also be involved in the Red Bull project, although primarily from an advertising perspective.

While talks between both McLaren, who are due to be powered by Mercedes for another three seasons, and Red Bull are at an early stage, Brown’s presence at Red Bull’s Milton Keynes headquarters was a surprise, given his strained relationship with rival boss Christian Horner following the cost-cap row which last year engulfed the sport.

Brown wrote a letter to FIA president Mohammed Ben Sulayem to suggest that a breach of the sport’s financial rules constituted “cheating”.

The American did not specifically name Red Bull, but the apparent insinuation infuriated Horner and has cast some doubt over whether the two teams would be able to work together in the future.

In a bitter press conference to preview October’s United States Grand Prix, Horner, sitting alongside Brown, said he was “shocked and appalled” by the accusation of foul play.

Red Bull were later fined £6million for a £1.8m overspend, although the FIA said they “did not act in bad faith, dishonestly or in a fraudulent manner”. Speaking at last season’s final round in Abu Dhabi, Brown said he stood by his letter.

McLaren are also understood to have been in dialogue with Honda as the Japanese manufacturer weighs up a formal return to F1 as an engine manufacturer in 2026.

Addressing McLaren’s future plans at his team’s launch last week, Brown said: “We have some time to decide what we want to do in 2026 and beyond.

“It’s something that (McLaren team principal) Andrea (Stella) and I are in the process of slowly reviewing. We’re not in a big rush and we are very happy with Mercedes.”

The PA news agency has contacted McLaren for comment.

The F1 season fires up in Bahrain next Sunday, with a three-day test – also in the Gulf Kingdom – getting under way on Thursday.