Brazil striker Neymar is reported to have decided to join Barcelona this summer.
Manchester City striker Sergio Aguero has underlined his commitment to the club by signing a one-year contract extension.
Guidetti has yet to play for City this season after being sidelined by injury, but was rewarded with a new three-year contract in October.
He impressed on loan at Feyenoord last season and his Italian representative Roberto De Fanti says Guidetti subsequently rejected a loan move to Siena last summer.
A January switch to Serie A has also been ruled out by De Fanti as Guidetti hopes to head out on loan this month in order to play first-team football.
"In the summer, the deal for Guidetti's transfer on loan to Siena was already done, then he talked with David Platt and decided to remain at City," De Fanti told Radio Blu.
"Now he is back after injury and he's looking for a team, but I think his most likely destination will be in England.
"A move to Italy could be possible for next season."