Holdsworth, 29, joined the Airlie Birds from Salford ahead of the 2013 season on a two-year deal, but according to his agent, has been discussing an early exit for personal reasons.
His possible departure hinges on Hull’s ability to find a replacement.
“It is something we have been aware of for some time and it gives us the opportunity to utilise space on the salary cap and budget to work with.
“We have a number of planned options to assess, but we will remain diligent in ensuring we look at all possible avenues around the world, including the World Cup over the coming weeks.”
Holdsworth made 22 appearances for Hull last season, scoring two tries and a total of 70 points.
He previously spent three years with Salford, having previously played in the NRL for St George and Canterbury.