The Wales international, who is said to have attracted a bid from Sunderland, is out of contract next season.
Manager Garry Monk has revealed that the Welsh outfit are in talks with Williams regarding a new contract, but nothing has yet been agreed.
"Ash has only got one year left on his contract, so clubs will look at that," Moralee told BBC Wales Sport. "If a new contract is not agreed or they don't accept one of the bids, Swansea could risk losing him for nothing.
"A bid has been made but nothing's been accepted or rejected yet - something has got to give. There are two or three clubs interested in Ash, and they must be confident in their ability to compete financially and be up there with Swansea in their offer for him."
The 28-year-old joined Swansea from Stockport County in 2008.