India goalkeeper Subrata Paul has tested positive for a banned substance, the All India Football Federation (AIFF) said on Tuesday.

"His sample A has tested positive," AIFF secretary Kushal Das told Reuters.

National Anti-Doping Agency chief Navin Agarwal confirmed the former India captain was tested by NADA officials in March but declined to elaborate further.

The 30-year-old was India's number one choice under the bar before slipping down the pecking order, behind Norway-based Gurpreet Singh Sandhu, in recent times.

Paul did not take calls when Reuters contacted him.

"It's now between him and NADA. He has to decide whether he wants his B sample tested," Das said.

"But of course if he needs guidance, the federation is always there."