Philadelphia 76ers guard James Harden has exercised his $35.6 million option for the 2023-24 season, clearing the way for the organization and the 10-time All-Star to work together on finding a trade, sources told ESPN on Thursday.

The Sixers started making calls on Harden trades Thursday as it became clearer that he wouldn't be declining the option and entering free agency, sources said.

Harden, 33, could've negotiated a new deal with the Sixers upon becoming a free agent, but he decided with president of basketball operations Daryl Morey that they would start working on a way to move Harden less than two years after his arrival in a February 2022 trade with the Brooklyn Nets, sources said.

Among the teams expected to have an interest in acquiring Harden are the LA Clippers and New York Knicks, sources said.

The Sixers are under no obligation to trade Harden, but it appears his focus is on finding a new team for the third time since leaving the Houston Rockets in February 2021. The Sixers could've offered Harden as much as a four-year, $213 million contract in free agency, but it was unlikely that they were going to make such a robust commitment to him.

Harden had an interest in a reunion with the Rockets -- who are flush with $64 million in salary cap space -- but their guard focus has increasingly been on pursuing Toronto Raptors free agent Fred VanVleet, sources said. Harden is hopeful of finding his way to a contending team in a trade scenario, sources said.

No formal talks on a free agent deal can take place before 6 p.m. ET on Friday, but the sides were allowed to discuss Harden's decision on the $35.6 million player option due Thursday.

Harden left as much as $15 million on the table a year ago by signing his current two-year, $68 million deal -- including a player option -- that allowed the Sixers the flexibility to sign free agents P.J. Tucker and Danuel House Jr. Harden had an All-Star-level season for the Sixers, averaging 21 points and a league-leading 10.7 assists. Philadelphia lost to the Boston Celtics in seven games in the Eastern Conference semifinals.

The Sixers acquired Harden after he expressed his desire to be moved to the Sixers. Harden and Morey have a long history, including nine seasons together with the Rockets.