Meghan Markle’s father may not attend her wedding, it has emerged, just five days before he was due to walk her down the aisle.

Doubts that Thomas Markle Sr, 73, would give his daughter away on Saturday followed claims by US celebrity website, TMZ, that he was pulling out amid allegations he cooperated with a Los Angeles based photo agency to stage pictures of himself preparing for the wedding day. Markle Sr had suffered a heart attack six days ago, TMZ claimed.

Responding to the report, Kensington Palace said: “This is a deeply personal moment for Ms Markle in the days before her wedding. She and Prince Harry ask again for understanding and respect to be extended to Mr Markle in this difficult situation.”

Kensington Palace had announced earlier this month that Markle Sr, a retired television lighting engineer who lives in Mexico, would walk his daughter to the altar at St George’s Chapel in Windsor Castle, where she will marry Prince Harry on Saturday in front of 600 guests and an international television audience of millions.

Her mother, Doria Ragland, 61, a social worker and yoga teacher who lives in Los Angeles, is expected to accompany her daughter in the bridal car. Markle was then planning to take her father’s arm on the steps of the chapel.

But TMZ said Markle had “now decided not to go because he doesn’t want to embarrass the royal family or his daughter”.

The development followed a report in the Mail on Sunday which alleged that Markle Sr had helped stage pictures showing him being measured for his wedding suit, working out with weights in a park, reading a book on British history and looking up reports in an internet cafe about the forthcoming wedding. The newspaper printed photographs which it claimed showed Markle and the photographer entering the cafe together.

TMZ reported that Markle Sr meant no harm to his daughter or the royal family when he allowed the photo agency to take the pictures and that he had not been motivated by money.

The website reported Markle had complained that at times over the past year he had been ambushed by paparazzi, often taking unflattering photos of him and that he had turned down offers for interviews of between $50,000 (£37,000) and $100,000. He thought the staged pictures would recast his public image.

TMZ added that Markle said he had suffered a heart attack six days ago, but checked himself out of the hospital so he could attend the wedding.

Earlier on Monday, Meghan’s half sister, Samantha, claimed on television that it was her idea that their father stage the photos.

Prince Harry has yet to meet his future father-in-law. Kensington Palace has previously said Markle’s parents would meet senior members of the royal family, including the Queen, in private this week. But it remained unclear on Monday night whether Markle Sr would be flying to London as planned.