The Premier League trio have been among clubs to send scouts to watch the 19-year-old in recent weeks playing for Belgian side Eupen.
Borussia Monchengladbach and Brugge have expressed interest in the exciting teenager, who tried and failed to push through a move to Celtic in January, however, he is aware of increasing interest from Premier League sides.
Onyekuru is predominantly a left winger but can play as a striker and on the right.
He has scored 15 goals this season including three in his last two games. The striker grabbed two in Eupen’s 2-2 draw with Roeselare before opening the scoring in a 2-0 win over Royal Excel Mouscron seven days later.