The 25-year-old, who made his grand prix debut for Williams at last year’s Sakhir Grand Prix when team regular George Russell was called up to deputise for Lewis Hamilton at Mercedes, will contest the next two rounds of the 2021 F2 season.

After opting against a return to F2 for a fourth successive campaign, Aitken instead switched to the GT World Challenge Europe series in a Lamborghini to broaden his skillset as a driver.

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But Aitken will make an unexpected return to F2 after receiving a call-up from the HWA squad to replace Matteo Nannini, who will now put his focus on his Formula 3 campaign.

"I was surprised but also very honoured that HWA asked me to support the team in Monaco and Baku,” said Aitken. “They are two of my favourite circuits and it is going to be a real pleasure!

“I know HWA from races in the past, in which we have competed against each other. I have always been aware of their high standard.

“I am looking forward to returning to Formula 2 and working with HWA, in order to get the absolute maximum out of the two weekends."   

Aitken, who is a four-time F2 winner, joins an HWA team that has managed just a single points finish so far this season, thanks to Nannini’s efforts to take 10th in the Bahrain feature race.

The British-born Korean will partner Alessio Deladda at the team for the upcoming races in Monaco and Baku.

"We are delighted to have acquired such a talented driver as Jack,” added HWA team principal Thomas Strick. “With his wealth of experience in the FIA Formula 2 Championship, he is sure to be a great help to us.

"In the case of Matteo, we will be focussing on the FIA Formula 3 Championship for the rest of the season. He has already shown his potential in that series at the start of the season.

“We now want to develop that potential and offer Matteo the best possible support on the rest of his career path. It is now important for him to continuously develop with regular successes.

“We feel this is the right step to sustainably develop and support him in the current phase of his promising career."