West Ham United admit it would be "difficult" to keep Dimitri Payet from joining Barcelona or Real Madrid this summer should either of the La Liga giants submit an offer for the France international. The 29-year-old has backed up an impressive debut Premier League season by leading France into the semi-finals at the European Championships with three goals in five matches – leading to him being linked with Chelsea.

The Mirror understands both the Blues – managed by Italian Antonio Conte – and Real are interested in the playmaker, who netted 12 goals and made 14 assists in 40 appearances in all competitions last term. The Sun understands the former Marseille midfielder is rated at £45m ($58m), over four times what the Hammers paid for him last summer.

Slaven Bilic, the West Ham manager, attempted to warn off interest in Payet throughout last season but suggestions he could leave the club have swelled following his showings at Euro 2016. Amid reports regarding Chelsea and Real's interest, co-owner David Gold says the club will battle to keep their prized asset but warns they may lose out to a big name.

"We'll fight tooth and nail to make sure Dimitri pulls on a claret and blue shirt next season," Gold told The Sun. "We want to improve our squad and Dimitri is an integral part of what we're trying to do. But we also must be realistic. If Barcelona or Real Madrid made a bid and he wanted to move there, it would be difficult to keep him. You can't have a great player like Dimitri and expect no one to make a bid, especially with the performances he's producing at the Euros.

"But the phone has not rung yet — although we know there's a chance it will once the tournament is over. We're not silly. Yet, let me be very clear, we would not welcome a call. The club certainly doesn't need to sell him so this is not a case of 'we've bought him for £10m and can now make a tidy profit'."

Chelsea and Real's hopes of luring Payet to pastures new this summer were defused by the player's agent Jacques-Olivier Auguste, who suggested he is ready to remain with West Ham, who move into the Olympic Stadium from this season. "He has a great contract with West Ham so I cannot see him leaving," he told The Guardian. "Dimitri is happy in London. You never know in football but only West Ham know what price they want if they decide to sell him."

While West Ham have made four additions already this summer, Chelsea have made just a single signing in the form of Belgium international Michy Batshuayi from Payet's former club Marseille. Conte is yet to formally begin his tenure in west London, having been on management duties with Italy at Euro 2016, but could be tempted to make further changes after the club's disastrous title defence last term.