(CNN) Film star George Clooney has called for a boycott of nine hotels because of their links to Brunei, where homosexual acts will from next week be punishable by death .

In an opinion piece written for Deadline, Clooney decried Brunei's announcement that from April 3 the country will stone or whip to death citizens caught committing adultery or having gay sex.

"Let that sink in. In the onslaught of news where we see the world backsliding into authoritarianism this stands alone," Clooney said.

He called for the public to join him in immediately boycotting nine hotels -- three in the UK, two in the US, two in France and two in Italy.

They include the Beverly Hills Hotel and the Bel-Air in Los Angeles, the Dorchester in London and Le Meurice in Paris.

Clooney said the Brunei Investment Agency owns the hotels, which he described as some of the "most exclusive" in the world. He even admitted he had stayed in some, until he found out who owned them.

"Every single time we stay at, or take meetings at or dine at any of these nine hotels we are putting money directly into the pockets of men who choose to stone and whip to death their own citizens for being gay or accused of adultery," he said.

"Are we really going to help pay for these human rights violations? Are we really going to help fund the murder of innocent citizens?"

Many of the hotels have refrained from commenting directly on Clooney's call for a boycott.

"Dorchester Collection's Code emphasises equality, respect and integrity in all areas of our operation, and strongly values people and cultural diversity amongst our guests and employees. Inclusion and diversity remain core beliefs as we do not tolerate any form of discrimination," the company said in a statement.

Le Meurice in Paris, did not have a comment but said they wanted to "stress that we do value LGBTQ rights," according to the hotel's press manager, Alexandra Chlopek.

But other international figures have aligned against the law.

Austrian Chancellor Sebastian Kurz called the law "cruel and inhumane."

"I call on the Sultanate of Brunei to withdraw the death penalty by stoning f homosexual acts between consenting adults," he said on Twitter.

"The same goes for other countries which have the same cruel & inhuman laws. No one should be criminalized based on their sexual orientation or gender identity."

Australian Sen. Penny Wong also tweeted that "Labor is deeply concerned by the Brunei government's plans to implement new laws that would see adultery and homosexual acts between consenting adults punishable by death."

Former US Vice President Joe Biden said stoning "people to death for homosexuality or adultery is appalling and immoral."

"Every single person on earth is entitled to be treated with dignity and to live without fear. There is no excuse -- not culture, not tradition -- for this kind of hate and inhumanity."

A penal code based on Sharia law

Brunei is a small oil-rich kingdom of just over 450,000 people on the island of Borneo, close to the more moderate Islamic nations of Indonesia and Malaysia.

In May 2014, Sultan Hassanal Bolkiah announced he would be imposing a new penal code based on Sharia law, an Islamic legal system which outlines strict corporal punishments.

At the time, the government's website quoted the Sultan as saying that his government "does not expect other people to accept and agree with it, but that it would suffice if they just respect the nation in the same way that it also respects them."

A new statement from the Office of Brunei's Prime Minister says the country has "always been practicing a dual legal system, one that is based on the Syariah (Shariah) Law and the other on Common Law."

The two systems will run in parallel starting April 3, the statement said, and will "maintain peace and order and preserve religion, life, family and individuals regardless of gender, nationality, race and faith."

"The Syariah Law, apart from criminalizing and deterring acts that are against the teachings of Islam, it also aims to educate, respect and protect the legitimate rights of all individuals, society or nationality of any faiths and race."

The roll out of the new laws was at the Sultan's discretion and on December 29 it was quietly announced that capital punishment for homosexual sex would be imposed in April. Theft will be punished by amputation under the new laws.

"Brunei must immediately halt its plans to implement these vicious punishments, and revise its Penal Code in compliance with its human rights obligations. The international community must urgently condemn Brunei's move to put these cruel penalties into practice," Rachel Chhoa-Howard, Brunei Researcher at Amnesty International, said in a statement.