Manchester City are being investigated by the Football Association regarding claims the club made an irregular £200,000 payment to the agent of Jadon Sancho when the forward joined from Watford in 2015.

The allegation was published by Der Spiegel on its website on Friday. The German publication reported that Sancho was represented by Emeka Obasi, who was given a £200,000-a-year scouting contract that was actually an “impermissible payment” by City to help facilitate the then 14-year-old’s move. A player cannot be represented until the year they become 16.

City offered the response they have given to Der Spiegel’s previous reports into the club and Uefa’s financial fair play regulations and players’ image rights. “We will not be providing any comment on out-of-context materials purported to have been hacked or stolen from City Football Group and Manchester City personnel and associated people,” a club statement said. “The attempt to damage the club’s reputation is organised and clear.”

The Guardian tried without success to reach Obasi for comment on Wednesday.

Der Speigel’s report is the latest to draw on information from the Football Leaks website. Sancho, now 18 and at Borussia Dortmund, moved from Watford to City for a fee of around £150,000.