Reigning Indian Super League champions Mohun Bagan on Monday bluntly refused to release their players for the ongoing national camp, stressing that it is "not mandatory" outside a FIFA window and accusing the All India Football Federation of "negligence" over player welfare.

The senior India squad began its preparatory camp in Bengaluru on August 15 ahead of next month's CAFA Nations Cup, but 13 players, including seven from Mohun Bagan, are yet to join the camp.

Initially, their absence was attributed to the club's Durand Cup commitments. But even after the Mariners crashed out with a 1-2 derby defeat to East Bengal in the quarterfinals here on Sunday, the club has stood firm, citing their upcoming AFC Champions League Two opener against Turkmenistan's Ahal FC at Salt Lake Stadium on September 16.

Hitting out at the federation, a Mohun Bagan official pointed to the case of skipper Subhasish Bose, who has been sidelined since suffering an injury during India's Asian Cup qualifier against Bangladesh in March this year.

"Every time they take our players, three-four of them return injured, and the AIFF is least bothered to communicate, compensate, or even check on them,” the official told PTI.

"Look at Bose... He is under rehab, has missed the entire season so far, we are paying his salary, and yet the federation hasn't even called once to inquire about him." He further added: "Unless it is a FIFA international window, it is not mandatory for the club to release its players as there is no compensation in case of injury. Hence, we are not releasing anyone for this camp." The seven Mariners missing from the camp include Anirudh Thapa, Deepak Tangri, Lalengmawia, Liston Colaco, Manvir Singh, Sahal Abdul Samad and Vishal Kaith. Forward Manvir is already nursing an injury.

Mohun Bagan have also denied the release of four youngsters -- Dippendu Biswas, Suhail Bhat, Priyansh Dubey and T Abhishek Singh -- who are with the India U-23 side preparing for next month's AFC U-23 Asian Cup qualifiers in Qatar.

"Abhishek is a vital cog in our defence in the absence of Bose, and so are Dippendu, Suhail and Priyansh. We will not release them either," the official said.

Bhat also has a niggle.

Mohun Bagan's defiance comes even as the AIFF, in its statement, thanked Jamshedpur FC for releasing coach Khalid Jamil "in the national interest" despite the ongoing season, and appealed for "cooperation" from all clubs.

The Mariners earned a direct entry to the AFC Champions League Two group stage by winning the ISL League Shield last season.

Following their September 16 opener at home, they face Sepahan SC (Iran) and Al Hussein (Jordan) in successive away fixtures, before hosting Al Hussein again on November 4.

Their campaign concludes with away and home ties against Ahal (November 25) and Sepahan (December 23).

FC Goa, who made the cut to the group stage after a 2-1 victory over Omani champions Al Seeb in the preliminary stage fixture, are in Group C and open their group campaign against Al-Zawrra of Iraq at home on September 17.

But four of their players -- Hrithik Tiwari (goalkeeper), defenders Boris Singh and Sandesh Jhingan and midfielder Udanta Singh -- have reported at the camp.

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