More than 1,000 passengers are being held on a UK-operated cruise ship in France after 49 people fell ill from gastrointestinal sickness.

Local health authorities in Bordeaux said three passengers had been isolated in their cabins on the Ambition, while other passengers will not be able to disembark in the port.

They added that there was "no reason" to link the outbreak to the hantavirus outbreak on a separate cruise ship.

The Essex-based Ambassador Cruise Line told the BBC a 92-year-old man had passed away on board on Sunday, but he did not report any related symptoms and his cause of death is yet to be established by a coroner.

The cruise operator added: "We are providing every support to the deceased's friends and family and extend our most sincere condolences to them at this difficult time."

Ambassador Cruise Line said in a separate statement that as of 11:00 BST on Wednesday, 48 passengers were displaying symptoms consistent with gastrointestinal illness, as well as one crew member.

The cruise ship set sail from Belfast on 8 May, before heading to Liverpool the next day.

There are currently 1,187 guests and 514 crew members onboard the ship, according to its operator.

In its statement, Ambassador said there was a reported increase in cases after guests boarded in Liverpool.

It said "a number of guests and crew onboard Ambition have displayed or are displaying symptoms consistent with gastrointestinal illness".

Gastrointestinal illness is a common condition that causes diarrhoea and vomiting. Cases in adults are usually caused by norovirus or food poisoning.

Carol Landa-Vance, who is from County Antrim and is on the ship with her husband, said she noticed on Sunday that "we were not allowed to help ourselves at the self service buffet.

"Condiments were removed and knives and forks were wrapped up and handed to us. The pools were closed and the jacuzzi was also closed."

She said that someone was sick on the bus in front of her, and another was sick on the deck.

"It's a wee bit scary but people are in mostly good spirits."

David Munster, from Dundonald in County Down, is on board with his wife. He said that after departing Liverpool they were informed that a number of passengers had "become ill".

Munster said: "At this stage we don't know if we will be kept on the ship and just have to sit here until this is dealt with, or whether we'll be allowed to get off and see Bordeaux, which is obviously what we'd love to do."

He said passengers were free to use the facilities that were open, but the people who were ill were isolating in their cabins.

Munster had not witnessed people being ill but had seen the "clean-up of people being sick" and said staff had been "very hardworking".

The cruise line said enhanced sanitation and prevention protocols had been implemented across the ship "in line with established public health procedures following the initial reports of illness".

Measures introduced since the initial reports of illness included increased cleaning and disinfection in public areas, as well as ongoing guidance to guests about hand hygiene and reporting symptoms to the onboard medical team.

Also on board is Michael Gallagher, from Omagh in County Tyrone. He has decided to stay in his cabin with his wife, avoiding the extra entertainment put on by staff.

He said: "Everybody's just a bit shocked. We've been on a lot of tours and have never experienced anything like this before."

A UK Health Security Agency spokesperson said it was aware of the outbreak but had not yet received confirmation of which illness is affecting passengers.

"French authorities are managing the outbreak and we are liaising with them regarding British passengers on board," the statement said.

As part of a scheduled stop at Bordeaux in southwest France, the operator said it had advised French health authorities of the situation.

A spokesperson for France's Department of Foreign Affairs and Trade said it "is aware of reports and stands ready to provide assistance".

The regional health agency for Nouvelle-Aquitaine said a medical team had been dispatched on board to assess the situation, with samples currently being taken to the Bordeaux University Hospital.

It added that passenger disembarkations had been suspended "as a precautionary measure due to the contagiousness of gastroenteritis-type illnesses" while tests were being processed.

The cruise operator said the results would take at least six hours to process.

"The health, safety and wellbeing of our guests and crew remains our highest priority, and we are sincerely grateful for the patience, understanding and cooperation shown while these precautionary measures remain in place," it added.