The IMO has laid out a framework on facilitating crew changes, as the Covid-19 outbreak has kept hundreds of thousands of seafarers either needing to come off their ships or join new ones.

The 12-step plan, circulated on Tuesday and developed alongside industry groups and unions, covers a seafarer's journey from home to the ship, including potential flights, as well as the trip back. The IMO is working with government authorities to implement the plan.

According to the International Transport Workers' Federation (ITF), 150,000 seafarers need to be changed over in two weeks, with tens of thousands stuck on their ships due to travel restrictions.

“This is about governments recognising the critical role that seafarers play in global supply chains, recognising them as key workers, and providing immediate and consistent exceptions from Covid-19 restrictions to allow crew changeovers," ITF general secretary Stephen Cotton said.

"International seafarers are bearing the burden firsthand as governments turn a blind eye to the ‘forgotten sector'.

"The ITF, [International Chamber of Shipping (ICS)] and IMO have a clear message, governments cannot continue with a mentality of out of sight, out of mind, and we strongly urge governments to use this roadmap to act now before we suffer more serious consequences."

The Covid-19 pandemic, which has infected nearly 3.7m and killed more than 250,000 globally, has forced seafarers to stay aboard their ships with many leading shipowners canceling crew changes earlier this year.

The seafarers who do disembark their ships have difficulty returning to their homes. Thousands of Filipino crew members are reportedly stuck in more than 40 countries after the Philippines banned all inbound flights for a week.

Seafarers working for cruise companies battered by the respiratory illness are stuck aboard their ships as the US Centers for Disease Control and Prevention places stringent requirements on repatriating crews.

In India, the crew of the 47,000-dwt Prem Mala (built 2000) is running low on supplies as the ship stays at anchor offshore Mumbai awaiting auction.

The IMO's protocols cover the responsibilities of shipping companies, seafarers and governments in getting crews to and from their ships, including social-distancing guidelines, personal protective equipment usage, documentation and medical examination, among other measures.

ICS secretary general Guy Platten said the industry has "stepped up and done the homework" to facilitate crew changes.

"The problem is simplistic, but the solution is complex," he said. "We are now working with governments to implement this roadmap.

“Seafarers continue to work really hard, day-in, day-out and far away from loved ones, but if we are not able to free our seafarers from their Covid-19 lockdown, we could start to see disruption to trade and, more importantly, we increase the risk of accident and occurrences of mental health issues. Putting this off is no longer an option.”