The 22-year-old forward moves to the London Stadium from Uruguayan club Deportivo Maldonado.

“I am very happy to have signed for West Ham,” he told the club’s website. “This represents a fantastic new challenge for me and I am really looking forward to it.

“The Premier League is the best league in the world and so I am delighted to have this opportunity to play in such a prestigious league.”

‘It is a new chapter for me and so I am excited to get started here and to fit in as quickly as possible, so I can be as useful as possible to my new team-mates and manager,’ said Calleri.

‘These are exciting times for me personally and I am motivated to adapt my game to this new environment.

‘I am a player who always tries to work as hard as I can and to do my best for the team.’ The young Argentinian, 22, trained for the first time with the Hammers on Tuesday after arriving from Uruguayan club Deportivo Maldonado.

Johnathan Calleri has scored 39 goals in 90 appearances in the last two seasons.