Former Dr Who actress Lalla Ward – whose family have links to Co Down – has separated from the UK’s best-known atheist, Professor Richard Dawkins.

On the death of the 6th Viscount in 1950 the house and estate were made over in lieu of death duties to the Government of Northern Ireland, which presented it and the gardens to the National Trust in 1952.

It is understood Ward – who played Dr Who’s sidekick Romana between 1979 and 1981 – has visited the property on a number of occasions.

She began her acting career in the Hammer Horror series in the early 1970s.

She had described her husband as “totally different” at home to the “outspoken” atheist he comes across as in public, stating “he doesn’t do emotional outbursts, get grumpy or depressed”.

After the couple married in 1992 Ward, who was previously married to Dr Who co-star Tom Baker, effectively ended her acting career, becoming a textile artist.

She has also co-narrated several audio books with her husband, and worked on the committee of the Actors’ Charitable Trust.

Ward is the daughter of Edward Ward, 7th Viscount Bangor, and his fourth wife, Marjorie Alice Banks.

William Maxwell David Ward, 8th and present Viscount Bangor, lives in London with his wife, the celebrated royal biographer Sarah Bradford, the Viscountess Bangor.

There is an apartment at Castle Ward for the use of Lord and Lady Bangor.

It is believed to be used by them mostly during the summer.

Dawkins and Ward had been married for 24 years.

The leading atheist, who suffered a minor stroke earlier this year, said their split was “amicable”.

It is understood they are both still living in the marital home in Oxford and remain friends.

They released a joint statement.

It said: “Our marriage, like everyone’s, is a private matter and we are not prepared to share any details.

“Suffice to say it is true that we recently separated entirely amicably.

“Obviously, this remains a difficult time, one which we simply will not discuss any further publicly. We would, however, like to stress that we shall always be friends and that we will, of course, continue to work together.”