The International Maritime Organization and four other United Nations agencies are calling for priority Covid-19 vaccination for seafarers.
The IMO is joined by the International Labour Organization, World Health Organization (WHO), International Organization for Migration and International Civil Aviation Organization in arguing that crews working on board the world's commercial ships should be fast-tracked for the vaccine.
They also asked that air transport workers be given priority.
"For shipping and air transport to continue to operate safely, the safe cross-border movement of seafarers and air crew must be facilitated," the five organizations said in a joint statement released on Friday.
"Seafarers and aircrew need to be protected through vaccination as soon as possible."
They said countries could begin requiring proof of vaccination to be allowed entry, despite WHO recommendations against such measures.
China and the United Arab Emirates reportedly have begun to require ships be crewed by vaccinated seafarers before being allowed to enter their ports.
The International Chamber of Shipping (ICS) has warned that the issue of so-called vaccine passports could severely affect shipping, with nearly half of the world's 1.8m seafarers hailing from developing countries, where vaccines could be hard to come by.
The chamber said governments must heed the joint statement.
"Crew are working hard around the globe to keep global trade moving, with 200,000 seafarers currently being impacted by overly harsh restrictions which stop them boarding or disembarking ships," ICS secretary general Guy Platten said.
“ICS and other organisations have been lobbying hard to get this recognition for seafarers and we urge governments across the globe to heed the call from the UN and recognise the fact that successful vaccination programmes will rely on those hidden heroes who deliver the vaccines and PPE around the world.
"Seafarers are a vital part of the vaccine roll-out and need to be vaccinated themselves and not forgotten."
The IMO, ICS and other industry and labour groups have been lobbying governments throughout the Covid-19 pandemic, first to allow crew changes, now on vaccination issues.
At the height of the crew change crisis, up to 400,000 seafarers were stuck on board their ships because governments would not let them off over concerns that the virus could spread further.
Some governments agreed and allowed crew changes, but many did not.
Since then, industry figures have warned that a lack of attention to the plight of crews could push seafarers out of the industry, leading to labour shortages.
