Eight Singaporean flight attendants who were part of the United Airlines' (UA) team based in Tokyo's Narita Airport are suing the airline in Japan over the termination of their employment last year.

They are among a group of 83 flight attendants who filed papers in February alleging unfair dismissal, a claim the American airline has reportedly asked the court to dismiss.

The group is seeking to be reinstated as employees of the airline, and want their salaries to be backpaid from the date they were "separated" - a term used by UA when notifying them of their dismissal last year.

The lawsuit comes after UA closed three of its international bases - one each in Germany, Japan and Hong Kong - on Oct 1 last year as part of its efforts to cut costs amid the Covid-19 pandemic.

It currently has only one international base, which is in London.

UA said during the announcement of the closures in June last year that over 800 jobs in the three bases would be affected.

While some crew members could relocate to the United States as they were eligible to work there, over 600 flight attendants found themselves at risk of losing their jobs, reported Hong Kong publication South China Morning Post in August last year.

In Japan, more than 200 flight attendants were eventually let go, according to local media reports.

When contacted by The Straits Times, the airline declined to comment on the civil suit in Japan.

Law firm Anderson Mori & Tomotsune, which represents UA in the lawsuit, also declined to comment when asked by ST if defence papers have been filed in court.

But Japanese media reports state that the airline has urged the Tokyo court to dismiss the lawsuit during proceedings last month, arguing that Japan does not have jurisdiction over it.

According to an English translation of the lawsuit document filed in court, the flight attendants claimed that their dismissal is invalid under Japanese labour laws.

They say four legal requirements for such dismissal were not satisfied: the necessity to reduce the number of employees; the suitability of efforts by the company to avoid the dismissal; the rationality of the selection of employees to be dismissed; and the reasonableness of the dismissal procedures.

Even if there has been a sharp decline in profits due to a drastic drop in international flights, the situation is likely to end or improve in the near future, the group argued in court papers.

The group also took issue with the airline's decision to offer voluntary furlough to flight attendants based in the US. They claimed that such an option was not given to them.

They were also not offered the opportunity to voluntarily retire with monetary payouts and medical benefits, which were available to other flight attendants based in London or the US, claimed the group.

They suggested that their own layoffs might have been a way for the airline to dismiss higher-paid employees.

Sekiya Law Offices, which represents the group in the lawsuit, told ST that the next round of oral proceedings is scheduled for next month.

The lawsuit may take more than two years to be resolved, the law firm said.

Singaporeans in the group that ST spoke to said they have already left Japan.

One of them, Mr Philip Leow, has since returned to Singapore.

The 65-year-old said he had been with UA for about 35 years.

Another Singaporean in the group, who wished to be identified only as Ms Soon, has joined her family in Australia.

She told ST that she had worked for UA for about 30 years, and it was her only job since she left school.