Roger Federer and Serena Williams are not going to participate in the third edition of the International Premier Tennis League because of financial issues for the exhibition series.

Mahesh Bhupathi, a player and managing director of IPTL, issued a statement Monday night blaming the "uncertainty of spending money" and the "current economic climate in India."

Bhupathi said he hoped Federer, the owner of 17 Grand Slam titles, and Williams, who has won 22 major singles trophies, would play in the IPTL in the future.

Federer has not played since re-injuring his surgically repaired left knee at Wimbledon in July.