Fran Villalba made his Valencia debut under former boss Gary Neville. Manuel Queimadelos Alonso/Getty Images

Manchester United have made contact over a potential deal for Valencia midfielder Fran Villalba, according to the youngster's agent.

Villalba, 18, made his La Liga debut in December last year during Gary Neville's time in charge and has made four appearances for the senior side, although he is currently playing for the club's B team in the Segunda Division B.

His agent, Vicente Fores, told Sport Witness that United have registered their interest with him, although negotiations are at an early stage.

He added it was "just a contact to know his situation" and, asked whether they are likely to make a bid soon, he said: "We've just started talking. It's up to United."

Valencia-based newspaper Super Deporte reported on Thursday that United are one of several suitors but said the Premier League side are the only club to have made any direct contact.

The report added that Valencia have arranged a meeting as they want Villalba to sign a new contract, with his current deal due to expire in 2018. Sport Witness said he currently has a €4 million release clause.

Fores added: "I don't know about Valencia, but I reckon they will make it hard."

Super Deporte reported that Villalba had been on the verge of signing a contract extension when former United defender Neville was sacked as Valencia boss in March and that negotiations then stalled amid doubts over his prospects at the club.