Boman Kohinoor met Prince William and his wife Kate in 2016.

Mumbai cafe owner Boman Kohinoor, arguably India's biggest fan of the British royal family, died on Wednesday, officials said.

The Parsi restaurateur "was suffering from cardiac issues and passed away at 4:45 pm (1115 GMT)," an official from Parsee General Hospital told AFP.

Boman Kohinoor was the star of a social media campaign in 2016 when his dream came true. He met Prince William and his wife Kate during their week-long trip to India and Bhutan.

"It is heartbreaking to report that the love of our life, Mr Boman Rashid Kohinoor, senior partner of Britannia & Co Restaurant, passed away at Parsee General Hospital," Mumbai-based blogger BombayWallah tweeted.

"He was 97 years old & Bombay's most beloved inhabitant."

Boman Kohinoor's father opened Britannia & Co Restaurant in Mumbai in 1923 and Mr Kohinoor worked there his whole life. The decor reflected his love of the British royals.

On the wall was a large, framed photograph of Queen Elizabeth II and next to it a portrait of Mahatma Gandhi.

The restaurant also had a giant cardboard cut-out of a grinning Prince William and Kate Middleton.

Mr Kohinoor wrote regular letters to Queen Elizabeth over the years and even received a reply from one of her representatives at Windsor Castle, an official royal residence.

Mr Kohinoor had a granddaughter named after William's late mother Princess Diana.