New York City Mayor Zohran Mamdani called for King Charles to “return” the prized Koh-i-Noor diamond, which the British Empire took from the Indian subcontinent in the 1800s, on the third day of the monarch’s state visit on Wednesday.

Before greeting Charles and Queen Camilla at a 9/11 memorial event, Mamdani was asked what he would discuss with the king if he had the chance.

“If I was to speak to the king, separately from that, I would probably encourage him to return the Koh-i-Noor diamond,” the leftist mayor said, adding that his focus would be honoring those killed in the terror attacks.

It’s unclear whether Mamdani followed through and brought up the contentious subject with Charles when the two met.

The monarch was seen laughing with Mamdani and having a brief conversation after they shook hands.

Housed in the Tower of London, the massive 106 carat stone is the star of Britain’s crown jewels, adorning the Crown of Queen Elizabeth the Queen Mother.

The ownership of the jewel has been contested over the centuries, passing through the hands of Mughal emperors, Iranian shahs and Sikh maharajas before the Kingdom of Punjab gave it to Queen Victoria in 1849 as part of a peace treaty.

India has repeatedly and unsuccessfully sought the return of the priceless jewel.

While there is little doubt it was mined in India, its history thereafter is a mixture of myth and fact, with several countries including Afghanistan, Iran and Pakistan also laying claim to the gem.

A politician from the anti-immigration Reform UK party was quick to slam the comments as an “insult to our King.” “This beautiful diamond is currently on display in the Tower of London,” the party’s home affairs spokesman Zia Yusuf said in an X post. “That is where it will stay”.