The 18-year-old England youth international had attracted the attention of several clubs once it became apparent he would not extend his stay with the Hammers, but it is Leeds who have won his signature.
Perkins made appearances in the Premier League and Europa League for the London club last season, coming off the bench against the Whites during Leeds’ 3-2 victory at the London Stadium, as well as featuring against GNK Dinamo Zagreb in Europe.
Son of former Ireland Under-21 international Declan Perkins, Sonny has represented England at several age groups and is currently an Under-18 international.
“Sonny becomes the club’s seventh summer signing, after the arrivals of Brenden Aaronson, Rasmus Kristensen, Marc Roca, Darko Gyabi, Tyler Adams and Luis Sinisterra,” a statement from Leeds United read.
“He will initially link up with the Under-21s side for the forthcoming season.”
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