Both players were allowed to head out of the KC Stadium on loan last season - ending the 2012/13 campaign at Ipswich Town and Blackburn Rovers respectively.
The pair have now entered the final year of their contracts at Hull and have been informed that they are free to find another club.
Neither would demand much of a fee, but no offers have been tabled as yet.
Bruce would be willing to keep McLean and Stewart if they cannot be shifted, but he will be leaving the exit door open throughout the summer.
He said in the Hull Daily Mail: "They're here and unless something happens in the transfer market for them, they remain here. It's as simple as that.
"I do think it's important that they go and play somewhere, but at the moment we haven't had any offers as such.
"I'm sure they'd both want to play more football this season, but that's not something I can guarantee here."