The Welsh club is reluctant to sell the 23-year-old during their battle for Premier League survival and are trying to price him out of a move to London.
West Ham reportedly made a bid worth £18m and might be willing to raise that offer to £20m but £40m is way out of their budget and valuation for the defender. One option could be a straight swap for former Swansea player Andre Ayew. The Hammers paid a transfer fee close to £21m for Ayew but they might consider trading him back to get their target.
With £75m paid by Liverpool for Virgil van Dijk the bar for inflated prices appears to have been set as the silly season opens for business tomorrow.