New Princess Diana murder theories 'not feasible,' say royal watchers

British authorities are assessing the “relevance and credibility” of new information related to the 1997 deaths of Princess Diana and Dodi Al Fayed.

Britain’s Metropolitan Police announced over the weekend that they have new information regarding the Paris car crash that killed Diana and Fayed, though they emphasized that they have not re-opened the case.

The shocker: An allegation that the Princess of Wales and her boyfriend were killed by members of U.K.’s elite special forces regiment, the SAS.

According to British media reports, the new information was given to London detectives by the parents-in-law of a British special forces soldier after his marriage fell apart.

The Sunday People newspaper reported that it had seen a seven-page, handwritten letter from the in-laws that alleged that soldier had boasted to his wife that his commando unit had been involved in Diana’s death.

“The Metropolitan Police Service is scoping information that has recently been received in retaliation to the deaths and assessing its relevance and credibility,” authorities said in a statement.

“The assessment will be carried out by officers from the specialist crime and operations command.”

Police stressed that they are not re-investigating the case, pointing out that a jury in 2008 decided that Diana and her boyfriend were unlawfully killed because of the “grossly negligent driving of the following vehicles and of the Mercedes" they were riding in.

Driver Henri Paul was over the legal alcohol limit when the car crashed in the Pont de l'Alma Tunnel in Paris on Aug. 31, 1997 while it was being followed by paparazzi. Paul also died.

Royal expert Robert Jobson told NBC’s “Today” show on Monday that there’s "there’s no evidence" to support the new claims concerning the tragedy.

"If Princess Diana had been wearing a seatbelt, she would have lived. So how on earth could this be an assassination?" Jobson said.

"The reality is Princess Diana wasn’t murdered. She was driven by a drunk driver at high speed being chased by the paparazzi."

Royal analyst Mark Saunders, author of “Diana and the Paparazzi” and other books about the princess told CNN that it’s “just not feasible” that British military would have had a hand in Diana’s death.

"I'm in my 40s now, and as long as I've been alive, every four or five years there's been another documentary, another book about the assassination of John Kennedy," Saunders said.

"And to some extent, Diana is rapidly becoming the new Kennedy. It's just continuous. It doesn't stop.

"People don't want to believe that someone as loved as Princess Diana can just die in a road accident. It just isn't enough. They want more."