The 23-year-old has been in excellent form for his Basque club during the 2019-20 campaign, scoring 12 times and contributing 12 assists in 42 appearances in all competitions.
Oyarzabal has a contract at the Anoeta until the summer of 2024, but according to Todofichajes, the Spain international could be on the move ahead of the 2020-21 season.
The report claims that Man United and Man City have both expressed an interest in his services as the pair look to boost their attacks in the upcoming transfer window.
Oyarzabal is believed to have a €70m (£64m) release clause in his current deal, although it has been suggested that he could be available for a figure in the region of €50m (£45m).
The attacker has managed 10 goals and 11 assists in 35 La Liga appearances this term. body check tags ::