PARIS (Reuters) - The hardline CGT trade union at Air France AIRF.PA has called on its members to refuse to work on U.S.-bound flights in protest against the U.S. immigration order that temporarily prevents refugees and travelers from seven Muslim-majority countries from entering the United States.

A passenger walks past an Air France logo at the Marseille-Provence airport in Marignane on the first day of a strike by Air France stewards, France, July 27, 2016. REUTERS/Philippe Laurenson/File Photo

The executive order by U.S. President Donald Trump has drawn criticism from airlines body IATA, which said its members were struggling to enforce unclear rules, faced additional costs and were worried they could be fined if they get it wrong.

Airlines have already juggled crew rosters to make sure staff holding passports from the affected countries don’t fall foul of the new rules.

On Tuesday, the CGT said Air France employees were within their rights to decline to work on U.S.-bound flights to object against what the union described as “anti-humanist” practices.

“Staff should let their managers know that they don’t want to work on affected flights,” Miguel Fortea, secretary general of CGT Air France, told French broadcaster BFM TV.

“Staff have a conscience; with political action, by refusing to apply the Trump order on French territory we can make start to make a change,” he added.

Air France, part of the Air France-KLM group, has come under fire on social media for preventing passengers from boarding as a result of the new rules.

In response, the carrier has said that like other airlines, it had to abide by immigration requirements of the countries that it flies to, which means not allowing passengers to board a flight to a destination where they would be refused entry.

It was not immediately available for comment on the union’s remarks on Tuesday.

Several lawsuits have been filed against the order, which the White House has said is needed to protect the citizens of the United States.

On its website, the CGT described the executive order as xenophobic and illegal.

The World Travel and Tourism Council (WTTC), which represents travel industry executives, said suspending travel based only on a person’s nationality or origin was wrong and called on the Trump administration to reconsider the ban.

“None of the shocking domestic incidents in the U.S. since 2001 have been attributed to external terrorists who have specifically flown into the country to commit an atrocity,” WTTC president and CEO David Scowsill said.

“Preventing ‘aliens’ from entering the U.S. for legitimate business or leisure purposes is misguided and counter-productive for the American economy.”