The Premier League outfit are reportedly close to securing a deal worth around £30million for the 25-year-old, who was also interesting fellow top-flight club Liverpool.

But it is Tottenham who have emerged as front-runners for the Brazil international's signature, and the Portuguese admitted negotiations had taken place.

"I can't really confirm anything regarding Willian," he said ahead of Tottenham's UEFA Europa League qualifying fixture with Dinamo Tbilisi. 

"But there is interest in the player and there have been conversations."

Roma winger Erik Lamela and Real Madrid full-back Fabio Coentrao have also been linked with moves to White Hart Lane.

However, Villas-Boas refuted claims any deals had been completed, but revealed the club will make further additions before the transfer window closes on September 2.

"None of the names you have mentioned have signed for Spurs," he added. "(But) we will see some new players in defence and attack."

The former Chelsea manager was also asked if Gareth Bale had already joined Real, after reports surfaced that Tottenham had accepted a £93million bid for the Welshman.

But Villas-Boas rejected these claims.

"I cannot say anything about that but it is not true (that he has already signed for Madrid)," he added. "Ideally we want to keep everyone."