The 63-year-old is being treated at the Royal Sussex County Hospital in Brighton.

Mrs Barnes, who presented the flagship News at Ten bulletin for a number of years, was admitted over the weekend after reportedly suffering a stroke.

In a statement, Knight Ayton Management, which represents Mrs Barnes, said: "Carol Barnes is seriously ill, and is being cared for at the Royal Sussex County Hospital.

"Her son James and close friends have asked for their privacy to be respected."

No details of Mrs Barnes' condition have been confirmed officially, but the Daily Mirror reported that she had suffered a stroke.

She began her working life as a teacher, before joining ITN as a reporter in 1976 and going on to anchor all the broadcaster's main news programmes.

After initially leaving ITN, she rejoined the news team for the war in Iraq as one of the main presenters on the now-defunct ITV News Channel.

Mrs Barnes had a long relationship with former government minister Denis MacShane, and their 24-year-old daughter Clare was killed in a skydiving accident in Australia in 2004.