It could persuade those Premier League club's monitoring his situation to make a move before the end of the January transfer window, something which looked unlikely when Downing injured his foot in the penultimate game of last season.
Aston Villa, who have been linked with a £20million double swoop for the Middlesbrough-born player and Turkey international Tuncay Sanli, are understood to be awaiting developments, while long-term admirers Tottenham, as well as Everton, have also been mentioned in dispatches.
Spurs made their latest attempt to sign Downing in January, but were rebuffed by chairman Steve Gibson.