They spoke of insufficient nourishment that has led to close relatives losing 20-30lbs in weight since they were sent to the Middle East five months ago, leaving one sailor “emaciated”, according to his mother.

They spoke also of low-quality drinking water and scarce mental health counseling and support despite the intense burden of being at sea for months on end without making land.

The USS Abraham Lincoln, an aircraft carrier with more than 5,000 sailors and marines onboard, has been at sea for nearly nine months, having begun its deployment in November. There have been reports of multiple suicide attempts including jumping overboard.

When Trump was asked on Friday whether naval families were worried about conditions on board, he replied: “No, they’re not.” He said that the Lincoln’s deployment, now in its ninth month, was “not nearly long enough”.