Eurostar passengers will be required to wear face masks from next week, as part of measures to cut close-contact transmission of the COVID-19, the company said on Saturday.

All the passengers must wear a face mask or face covering at the stations and on board conforming to guidelines announced by the French and Belgian governments, according to a notice from the company's website.

UK-based Eurostar has been running a reduced timetable since the outbreak of the coronavirus, due to movement restrictions, enhanced border checks and lower demand.

The French and Belgian authorities warned its passengers on cross-Channel trains between London, Paris and Brussels that anyone not covering their mouth and nose may be refused to travel or fined. The measures are among several to be introduced as governments on both sides of the Channel look at easing stringent lockdown restrictions.

Catering facilities on trains and in stations have been closed, and special assistance suspended due to social distancing requirements, the company said on its website.

It also advised passengers that France was restricting travel to EU citizens of mainland continental Europe returning home to their main residence.

UK and non-EU citizens with a residency permit in an EU country, plus essential workers, were allowed to travel, it added. But all passengers required additional paperwork in France to show their trip was essential.

Belgium, which has had the highest per capita rate in the world, 67 per 100,000 people, stars to lift its lockdown on Monday. Its method of compiling data imputes some deaths to COVID-19 even if a test has not confirmed it, which is not the case in many other countries.

Meanwhile, all passengers travelling on public transport in Belgium are required to cover their mouth and nose, otherwise, they will be fined.

France, which has had nearly 25,000 deaths, has made a similar requirement. It is gradually easing its restrictions from May 11.

Britain, which has had more than 28,000 deaths, has not required the public to wear masks, although Prime Minister Boris Johnson this week indicated they could be "useful" when restrictions are lifted.

(With input from agencies)