Swansea are insisting on £18million for defender Joe Rodon who is the subject of a £7m offer from Tottenham.
The centre back is a product of the Swansea academy and broke into the first-team in 2018 and helped Steve Cooper's side reach the Championship play-offs last season.
Tottenham's £7m offer is understood to have been rejected with Leicester also said to be interested in making a move for the defender before Friday's EFL transfer deadline.
Jose Mourinho has already brought in defensive reinforcements with Matt Doherty and Sergio Reguillon joining in the summer.
Rodon has made a total of 49 appearances in all competitions for the Swans, with all of them coming while they have been in the second tier.
He was called up to the senior Wales squad for the first time in 2018 though did not make his appearance until a year later - with his international debut coming in a Euro 2020 qualifier against Azerbaijan.
He was part of the Wales team that lost 3-0 to England on October 9 at Wembley but also featured in the 0-0 draw with the Republic of Ireland and the 1-0 victory over Bulgaria.
Meanwhile, Swansea striker Andre Ayew's proposed move to Brighton has stalled.
Brighton, however, retain interest in free agent Danny Welbeck.