The 22-year-old wing, who has been a key performer for Wales since breaking into the team in 2020, has scored 14 tries across 31 Test caps, and toured with the British and Irish Lions in 2021.

Rees-Zammit has scored 38 tries in 69 appearances for Premiership side Gloucester, and most recently scored five tries in five Rugby World Cup appearances for Wales in France.

Gloucester confirmed the immediate release of Rees-Zammit from his contract, with the player announcing the move mere minutes before Warren Gatland confirmed his Wales squad for the 2024 Six Nations.

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Rees-Zammit said: "Gloucester Rugby has been a huge part of my life. From the start at Hartpury College and my first professional rugby contract with Gloucester in 2020, to my Wales and Lions caps; the club has been central to my development as a player, and I'm so grateful for their support.

"I will always be very proud of my time at Kingsholm and want to particularly thank the incredible fans who make the club so special. Also, to my teammates, to George Skivington and Alex Brown, thank you for giving me such special memories and for supporting this next stage of my career.

"I have had the incredible honour of playing rugby for my country which, as a proud Welshman, I've never taken for granted. However, I believe that this is the right time for me to realise another professional goal of playing American football in the US. Those opportunities don't come around very often."

The news is a particular blow to Gatland and Wales, with a number of experienced players having departed the set-up in the form of fly-half Dan Biggar and full-back Leigh Halfpenny retiring since the World Cup, and back-three Liam Williams moving to play club rugby in Japan. Second row Alun Wyn Jones and back-row Justin Tipuric retired before the tournament.

Wales also have a number of injuries at present to talented back-row Jac Morgan, who was named co-captain of Wales at the World Cup and will miss the rest of the season due to a knee injury, hooker Ken Owens (back), No 8 Taulupe Faletau (arm), Christ Tshiunza (foot) and Dewi Lake (hamstring).

Commenting on the announcement Gloucester chief executive officer Alex Brown said: "We understand the size of the opportunity before Zam and his lifelong ambition to play in the NFL.

"Whilst we are naturally sad to see him leave, ultimately, we are not able to dissuade him from taking an opportunity of this magnitude with the NFL.

"We remain very proud of the role Gloucester Rugby has played in helping to develop him into the world-class player he has become, and we wish him the very best in the US. He will always be welcome at Kingsholm."

What is the International Player Pathway Programme?

The IPP was launched by the NFL in 2017 as the brain-child of British Dallas Cowboys coach Aden Durde in view of providing athletes from outside of the United States with an opportunity to vie for a spot on an NFL roster.

Rees-Zammit will join a select group of elite athletes to train in the United States as they look to demonstrate their physical attributes before the eyes of NFL team scouts in hope of being picked or assigned to an NFL practice squad.

Since the program was launched 37 international players have signed with NFL teams, whether it be through allocation, the draft or as a free agent.

Australian Philadelphia Eagles starting left tackle Jordan Mailata has emerged as the programme's largest success story after converting from rugby to football, while British defensive end Efe Obada has played six seasons in the NFL after coming through the IPP.

Among the most high-profile rugby players to attempt the transition is Christian Wade, who spent three years on the Buffalo Bills practice squad after being released by Wasps in 2018. Wade has since returned to rugby to play for Racing 92.

The UK's Ayo Oyelola (Jacksonville Jaguars) and Adedayo Odeleye (Houston Texans) both came through the programme in 2022, before a record eight athletes were assigned to teams during the 2023 cycle, including six from Osi Umenyiora's Uprise programme in Nigeria.