The transfer of French teenage forward Kylian Mbappe from Monaco FC to Paris Saint-Germain (PSG) was the most successful transfer deal in the history of football, Vadim Vasilyev, the vice president of the principality club, said on Monday.

Mbappe, 18, joined PSG on a season-long loan, but the French football club has an option to buy him out on a deal until June 30, 2022. According to L’Equipe, Paris Saint-Germain will pay for the deal 180 million euros ($214 million).

“It was a very tough deal,” Vasilyev said in an interview with Tass news agency. “Initially, we did not want to let the footballer play for our opponent. I have cultivated very good relations with the player and his parents, particularly with his father, who also acts as his agent.”

“When I heard their opinions regarding why he wants to move to Paris, I accepted them and we began difficult and tiresome negotiations with PSG,” he said. “I think that this deal turned out to be the most successful in the world of football.”

According to Vasilyev, the deal’s price tag was within the market framework and Monaco FC had proposals similar to those of other clubs as well.