Swansea chairman Huw Jenkins believes Gylfi Sigurdsson is 'priceless'.
The Iceland international is being pursued by Everton, who have had the midfielder listed as a target since last summer.
The 28-year old played a pivotal role in helping the Swans avoid relegation last season and Jenkins believes it's hard to put a price on his value.
"We've not had any firm bids and if we ever get any firm bids then we will deal with them in the proper way," Jenkins told Sky Sports.
"Our aim is to try and keep Gylfi and Fernando, keep our better players and to make sure we can add to Paul's [Clement] squad.
"It's hard to suggest what sort of value Gylfi has in today's market, but to us he is priceless and we've got to make sure we do everything in our power to make sure he stays with us."