The Duchess of Sussex's father, Thomas Markle, is in intensive care after undergoing emergency surgery.

Markle, who is 81, was hospitalised in the Philippines on Tuesday after an undisclosed illness that required medical attention.

His son confirmed the news to the Daily Mail several hours after the event.

"I took dad to a hospital close to our home, and they did various scans, and the doctors said his life was in imminent danger," Thomas Markle Jr told the outlet.

"They raced us by ambulance, with the sirens going, to a much bigger hospital in the centre of the city."

He added, "My dad has undergone emergency surgery. I would ask everyone around the world to keep him in their thoughts."

According to Thomas Jr, the former TV lighting director now needs a second procedure in order to remove a blood clot.

Markle's eldest daughter, Samantha Markle, has also shared her wishes for a swift recovery.

"He is a strong man, but he has been through so much. I am praying that he is strong enough to survive this," Samantha told the Daily Mail.

"My father has been through two heart attacks, a stroke and an earthquake. I hope he can pull through this."

Thomas Jr and Samantha are Markle's children from his first marriage. He also shares Meghan with ex-wife Doria Ragland.

Neither the Duchess of Sussex nor her mother have publicly addressed Markle's most recent health scare.

The Suits alum has been estranged from her father since 2018 after he was accused of staging paparazzi photos before her marriage to Prince Harry.