LONDON (Reuters) - Over 300 leading companies said on Tuesday they would work together to help hundreds of thousands of merchant sailors stuck on ships for many months due to COVID-19 in a crisis that risks creating more dangers at sea. About 90% of world trade is transported by sea, and coronavirus restrictions in many jurisdictions are affecting supply chains. In December the U.N. General Assembly urged all countries to designate seafarers and other maritime personnel as key workers. Nevertheless, ship crews are still struggling to swap over with colleagues on land. Shipping industry officials say many sailors are at breaking point and many have been at sea for longer than an 11-month limit laid out in a maritime labour convention. The companies, which include shipping groups such as A.P. Moller Maersk, miners Anglo American and Rio Tinto, oil majors BP and Royal Dutch Shell as well as trading companies Cargill, Trafigura and Vitol, will boost information sharing as signatories of the “Neptune Declaration” initiative. “All of us have a duty of care to seafarers,” said Kit Kernon, global head of shipping at Vitol. “Their wellbeing is essential to safe and efficient operations.” Signatories will also increase collaboration between shipping operators and charterers to speed up crew changes while also calling for key worker status for mariners. “We are witnessing a humanitarian crisis at sea,” said Jeremy Nixon, chief executive of shipping group ONE. “They have become hostage of the situation and unable to disembark from their ships.” Sven Boss-Walker, senior vice president of shipping at BP, said the “remote nature of their roles meant their contributions are often out of sight and out of mind”. “It is critical that the industry comes together to provide a collaborative response,” Ashley Howard at Rio Tinto added.