Colchester boss Aidy Boothroyd told BBC Essex: "The plan is to make it permanent. He's a very good player, he's been there and done it.
"In a team that's growing we've got to have people in the dressing room and out on the pitch who can lead."
Former Southampton, Nottingham Forest and England Under-21 midfielder Prutton said he was pleased to be linking up with Boothroyd after falling out of favour at Elland Road.
"I loved it, it was good fun, it seems like a good set of lads which I think is the most important thing," he said.
"If you can get on with people then you can express yourself and play the way you know can."
Source: BBC Sport