Dundee United say they have rejected offers in excess of £1m for two of their players from English clubs.
But the Tannadice outfit will not reveal the identities of the transfer targets and insist they are not under any pressure to sell.
However, BBC Scotland has learned that enquiries have been made about striker Johnny Russell, winger Gary Mackay-Steven and defender Gavin Gunning.
The trio impressed as United finished fourth in the Scottish Premier League.
With one match remaining, Russell has scored 14 goals this season, while Mackay-Steven has found the net five times and Gunning has pitched in with three goals.
Mackay-Steven is under contract until the summer of 2015, while fellow 22-year-old Russell has 12 months less to run on his deal, along with Irishman Gunning, 21.
United will see departures over the summer, with goalkeeper Dusan Pernis, defenders Gary Kenneth and Paul Dixon and midfielder Scott Robertson all choosing to leave under freedom of contract.
Midfielder John Rankin has agreed to stay on for another year after a good first campaign at Tannadice.