Pakistan's ace spinner Saeed Ajmal has brought the curtains down on his cricket career with a "heavy heart", criticising the ICC's protocol to assess bowling actions on his way out.

After a successful but controversial career, off-spinner Ajmal finished with 178 wickets in 35 Tests, the last of which was at Galle in Sri Lanka in 2014, where his bowling action was reported for a second time.

His action was first reported during an ODI series against Australia in the UAE in 2009.

His time in the limelight cut short following a temporary ban for chucking, Ajmal returned to the sport in 2015 with a re-modelled action but without much success.

"I am retiring today and at 40 years of age I thought it is now time for me to make way for younger players," Ajmal told PTI.

"I am retiring with a heavy heart because firstly I think the ICC's protocol is too harsh and if all bowlers today playing international cricket are tested I am sure at least 90 percent will fail to clear this protocol," Ajmal said.

He felt that if the Pakistan Cricket Board had fought his case more vociferously at the ICC, he would have left a satisfied man.