(CNN) - Joaquin "El Chapo" Guzman's complaining about lack of outdoor activity may be part of a plan to escape from detention before his sentencing next month, federal officials allege.
An attorney for Guzman this month asked a federal judge to intervene over "cruel and unusual" prison conditions for the drug kingpin detained in a federal prison in New York.
In the more than two years he's been detained, he's not had access to fresh air or natural sunlight, and is forced to put toilet paper in his ears to mask loud prison noise, his attorney wrote in a letter to the judge.
The United States issued a response to the allegations Thursday, saying the only outdoor exercise space at the facility is a rooftop with a wire mesh covering.
That facility was the site of a 1981 attempted jail break -- where an inmate's cohorts hijacked a sightseeing helicopter and attempted to cut open the wire mesh covering, the US said.
"In this case, any outdoor exercise time would be particularly problematic for this defendant," the US said.
" The defendant has successfully planned and executed elaborate escapes from two high-security penal institutions. As detailed at trial, one of the defendant's escapes involved the construction of a sophisticated, ventilated tunnel that stretched for over a mile. Certainly, an escape via rooftop, using a helicopter, or any related means would be elementary by comparison."
He will be sentenced next month
Guzman, once the leader of a murderous drug cartel in Mexico, was convicted in February of running a criminal enterprise and other drug-related charges. He will be sentenced on June 25.
He's been in US detention for 27 months, and is in solitary confinement in a 10-by-8-foot windowless cell in Manhattan, according to his defense attorney, Mariel Colon.
In the letter to the judge, the attorney described what she called a series of punishments against the drug lord. The light is always on in his cell, leading to a "serious issue of sleep deprivation," she wrote.
In addition to the lack of light, the air conditioning in his cell is so loud, he is unable to sleep through the noise, his attorney said. As a result, Guzman has been using toilet paper as earplugs, and he complains of daily headaches and ear pain that makes it impossible for him to use earphones.
"The reason for the restriction is simple: If there were an emergency, an inmate would not be able to hear the guards alerting the inmates to the problem. Inmates could also use the earplugs as a ruse to ignore, or pretend not to hear, the guards' orders," the government said.
The defendant has a week to respond
The attorney asked the judge to order the Bureau of Prisons to grant Guzman access to two hours of outdoor exercise a week, earplugs and the same food and drink offerings as other inmates.
But the government said he has access to "several different types of exercise equipment, including an exercise bike and elliptical, and a vented window that provides the defendant with access to fresh, outdoor air and sunlight."
The US Attorney's Office for the Eastern District of New York and the Bureau of Prisons declined to comment when reached by CNN this month. The judge had ordered the government to respond by May 23 and the defendant a week later.
The government has called for Guzman to be placed under restrictive detention conditions to prevent him from running the Sinaloa Cartel from prison, coordinating an escape from prison, or directing attacks on individuals he believes are cooperating with the government, according to the filing.