Like other European monarchs, Luxembourg’s Grand Duke Henri is limited to a ceremonial role — but no law can go into effect without his formal assent.

So when he stunned his 480,000 subjects by refusing to give his royal blessing to a euthanasia law adopted by parliament, this tiny country shoehorned between Belgium, Germany and France was thrown into crisis.

On Thursday, the 60-member legislature votes on a constitutional change that strips Henri of his power to “approve” legislation adopted in parliament, limiting him only to announcing — or “promulgating” — the decisions made by lawmakers.

The legal tweak, which is set to pass easily, makes it possible for the euthanasia bill to become law and prevent future crises of conscience at the gingerbread palace in the cobblestoned capital.

It’s not the first time a monarch has been muzzled to make way for a law.

In 1990, the Belgian government made King Baudouin a commoner for a few days when he refused to sign an abortion law. He was put back on the throne after the legislature enacted the bill unilaterally.

The devoutly Roman Catholic Henri, 53, doesn’t seem too bothered by the royal downgrade: according to Prime Minister Jean-Claude Junker, the Grand Duke and his wife Maria Teresa approve of Thursday’s proposed change.

A Dec. 3-4 poll said 60 percent of Luxembourgers disapprove of the Grand Duke withholding royal assent, 69 percent want him as a “purely ceremonial” monarch and 70 percent back the euthanasia law parliament adopted on Feb. 18 in a 30-to-26 vote.

These finding appeared at first to boost Juncker’s chances of quickly resolving the constitutional crisis. But some in his long-ruling Christian Democratic party now have second thoughts and fear Thursday’s vote may trigger a divisive referendum on the Grand Duke’s role and powers. It takes only 5 Luxembourgers to launch a referendum if they can produce 25,000 signatures.

Frank Engel, secretary general of the Christian Democratic parliamentary delegation, sees conservative Catholics agitating to portray the monarch as a defender of ethics. “If it comes to a referendum the euthanasia law will get entangled with the issue of the monarch’s constitutional duty,” says Engel. “These are two very different matters.”

Guy Arend, an elderly Luxembourger shopping on a busy street near the grand ducal palace, said it is wrong “for parliament to change the constitution. It means the Grand Duke will no longer be able to vote with his conscience.”

Euthanasia has been debated here for over a decade. Luxembourg legalized abortion in 1978, a bill Henri’s father signed without protest. The new law makes euthanasia possible after at least two doctors have been consulted.

It was largely written by Jean Huss, a Green parliamentarian and right-to-die activist, who sees much “opposition from the Vatican which fears, of course, a domino effect, that Germany, Italy and other European countries will follow suit.” Luxembourg would be the fourth country to legalize euthanasia after the Netherlands, Belgium, Colombia.