Gary Carr has been unveiled as Downton Abbey's first ever black character.

The Death In Paradise star will join the cast of Julian Fellowes' ITV1 period drama for the fourth series, as jazz singer Jack Ross.

The 26-year-old actor will take on the role of Ross, who is described as "a charming and charismatic young man". His character will play a singer at an exclusive club in the 1920s.

Carnival Films' managing director Gareth Neame said Carr's addition to the cast "will bring interesting twists to the drama which we can't wait for viewers to see in series four."

"We are delighted to introduce another fantastic, dynamic character to Downton Abbey," he added.

In 2012, Fellowes revealed plans to introduce a black or Indian character in attempt to "open the show up ethnically".

Carr is just one of several new cast members to join the drama, with Dame Kiri Te Kanawa, Julian Ovenden, Nigel Harman, Joanna David and Dame Harriet Walter all signing up for the show.

Downton, which counts President Obama's wife as one of its biggest fans, ended its last series on a high after becoming the most watched drama programme of 2012 with an average of 11.9 milion viewers.

It has also broken records since launching in the US, with the finale for the third season being the highest-rated show on American television that evening, with an average of 12.3 milion viewers.

The Obamas are apparently so hooked on the British costume drama that the First Lady wrote to ITV1 in November requesting some DVDs of the new episodes before they hit US TV Screens.

An ITV spokesperson told the Sun: "We'd heard the Obamas liked to watch it but we were very surprised when someone from the First Lady's office got in touch asking for the series.

"They were very polite and we were more than happy to sort out some DVDs to send over."