Amnesty International is weighing in on behalf of accused Mexican drug lord Joaquin “El Chapo” Guzman Loera, seeking permission to visit the federal jail in Manhattan where he is being held awaiting trial to assess whether conditions are too harsh.

The request, revealed in a letter late Wednesday from Guzman’s legal defense team to U.S. District Judge Brian Cogan in Brooklyn, is the latest salvo over tight security and restrictions on visitors for the alleged drug trafficker, who twice escaped prisons in Mexico.

Amnesty deputy directory Justin Mazzola said in a March 28 letter to prosecutors that the group is concerned that conditions at the Metropolitan Correctional Center are “unnecessarily harsh” and may “breach international standards for humane treatment.”

He said lights are on 24 hours a day in the section of the jail where Guzman is held, he is confined to his cell for 23 hours a day with only an hour of exercise, he has not been allowed visits or calls with his wife or other family members, and he can’t communicate with guards because they don’t speak Spanish.

“There is a considerable body of evidence . . . that prolonged isolation can cause serious psychological and physical harm, particularly if accompanied by other deprivations such as lack of information about the outside world, confinement to an enclosed space and inadequate exercise,” Mazzola wrote.

The government has contended that the tight security and restrictions on communications with his wife are needed because in addition to the escapes, Guzman has been able to continue to run his Sinaloa Cartel drug operations from prison through intermediaries.

Guzman is currently represented by federal public defenders. Defense lawyers Michelle Gelernt and Michael Schneider have previously complained that the restrictions are so tight that the accused drug kingpin has been unable to access money to hire a private lawyer.

They asked Cogan to order prison officials to lift the special security restrictions, transfer Guzman into general population at the jail and approve the visit by Amnesty International.