The westerners are said to be trapped in quarantine, sharing videos and pictures with the outside world as they wait in limbo.

To keep their spirits up the group were filmed singing and drinking around a table in a hotel.

Authorities in western Mongolia, which is close to the Russian frontier have instituted a quarantine to prevent the bubonic plague from spreading.

The tourists - seen wearing face masks when outside - are barred from leaving Uglii, population 28,000, and remain at a local hotel.

Reports in Russia say American, Dutch, German, Swedish, Swiss, and South Korean tourists are marooned in the city.

Footage emerged of an international group happily singing a Swedish song to keep up their spirits with a feast during the plague - but it is known they have pleaded with the Mongolian authorities to tell them when they can depart.

Separately, dramatic pictures from capital Ulaanbaatar have shown at least one aircraft being met by anti-contamination emergency workers in a bid to prevent the spread of the disease.

The tragic Mongolian couple who died from the plague got infected after eating the raw kidneys of a marmot, it is understood.

The city is closed due to some plague-contaminated marmots.

The man named Citizen T, aged 38, died on 27 April after hunting and eating a marmot, then his pregnant wife, 37, died three days later.

Russian tourists told of the lockdown preventing the international travellers from leaving.

“The city is closed due to some plague-contaminated marmots,” wrote traveler Elena Kovena from Kemerovo in Siberia.

“This is just so surreal.”

She said: “Did you think that the plague was something from the Dark Ages?

“Us too.

“We were just about to leave Ulgii to go deeper into Mongolia, but all exits of the city were shut and we were not allowed to leave.”

“We were told to wait for updates on Monday, 6 May,” said one named as Timur Konev.

From a local hotel, he said: “Six nationalities got together earlier today to plan the escape route.

“We spoke to local administration, to local police, but they didn’t allow us out.”

Neighbouring regions of Russia were said to be on “high alert”.

In Uglii a total of 158 people who came directly or indirectly into contact with the couple are ‘under supervision’.

The plague is a bacterial disease that is spread by fleas living on wild rodents such as marmots.

The disease can kill an adult in less than 24 hours if not treated in time, according to the World Health Organisation.

The plague is believed to be the cause of the Black Death that spread through Asia, Europe and Africa in the 14th century, killing an estimated 50 million people.