Thousands of US military members who have been living aboard an aircraft carrier for more than 250 days are reportedly contending with food shortages, broken plumbing, exhaustion, and other hardships, leading lawmakers to demand answers from the Pentagon and putting pressure on the Trump administration over the Iran war.

Military news outlets reported that multiple sailors on the USS Abraham Lincoln have considered jumping overboard, as well.

Defence Secretary Pete Hegseth on Thursday called reports of poor conditions "completely misrepresented".

The carrier left California in November for the South China Sea and was sent to the Middle East ahead of attacks on Iran in February.

The deployment, which was originally set to end in May, has been repeatedly extended. No return date has been announced, but on Thursday multiple outlets reported the US is preparing to replace the carrier with the USS George Washington as part of a previously scheduled rotation plan.

The BBC has contacted the Pentagon about those reports.

Connecticut Senator Richard Blumenthal listed the reported hardships on the carrier, where about 5,000 people are on board, in a letter to Hegseth: "Shortages of basic supplies, water contamination, plumbing issues, deteriorating mental health, deck safety concerns, and disruptions in the mail system, which have caused many care packages in route to the ship to be lost in transit for months."

"These reports warrant immediate attention," the Democrat, who serves on the Armed Services Committee, wrote, "but they also raise a broader question: whether the Navy can sustain the operational tempo now being demanded of its carrier force."

Fellow Democratic Senator Ruben Gallego called for the military to allow a congressional delegation to visit the ship.

"The Department of the Navy must allow a bipartisan Congressional Delegation to visit the USS Lincoln to conduct oversight investigation into this horrible situation," he posted on X, adding: "There is no reason to be denied access."

Citing two unnamed officials, CBS News, the BBC's US partner, reported that earlier this month a sailor went overboard and was recovered by a helicopter, treated by the medical department, and transferred off the ship for further care.

The circumstances of the incident are currently under investigation.

The Military Times and Stars and Stripes reported earlier this week that multiple service members had considered suicide by jumping overboard, according to their families. They said that being at sea for an extended period of time and the conditions on board were hurting some members' mental health.

Those conditions also reportedly included not being able to clean laundry for more than a week and not eating fresh food due to infrequent visits to ports, when troops are not always allowed to leave the ship.

Following those reports, a Navy official told the BBC they had not identified an increase in reported suicidal ideation or suicide attempts aboard the ship and that "traditional supply hubs" had been "disrupted by combat actions".

The Navy was currently putting a priority on delivering "mission-critical supplies" to the ship.

"First food, then hygiene items, then mail," the official said on Wednesday. "Current reports from the ship confirm continuous access to clean water, functional AC (air conditioning), and healthy meal options."

Hegseth, while speaking to reporters in Panama on Thursday, said the government makes sure "every ship, every crew, every captain has everything we can provide them at every single moment".

"Some deployments are longer than others, and I have more respect and gratitude for those sailors than anybody," he said. "What they do in those high seas in those austere conditions with less port calls - it's incredible."

Asked about the conditions on board, Olivia Wales, a spokeswoman for Trump, told reporters that both Hegseth and Trump were committed to ensuring the US military was "equipped with the resources necessary to counter any threat to the United States".

During other lengthy deployments, the Navy took steps to provide entertainment for troops, according to military publication Stars & Stripes, including bingo, art sessions, and a singing contest.