The Hollwood star George Clooney visited Gordon Brown in Downing Street today to highlight the crisis in Darfur.

The 46-year-old actor and director has become a high profile advocate to tackle problems in the region and took up a role as United Nations "messenger of peace" earlier this year.

Clooney, who arrived in London for the red carpet premiere of his new film Leatherheads, paid a visit to Mr Brown earlier today and posed for pictures with the Prime Minister as well as his wife Sarah Brown.

Speaking later to reporters at London's Dorchester Hotel, where he was promoting the movie, Clooney highlighted the need for helicopters to transport people to places where they can be protected.

He said that a "wonderful suggestion" had been made at the meeting about a fund which could involve leasing or buying helicopters "to create some security".

Clooney said it was also mooted that London could be a place where rebel leaders meet.

Mr Brown later added to Clooney's comments, describing the situation in Darfur as unacceptable and saying he was grateful for Clooney's leadership.

Mr Brown said: "In February and March alone, fighting displaced 58,000 people.

"Humanitarian access is limited and Unamid (United Nations African Union Mission in Darfur) deployment is still too slow.

"The rebels and government continue to openly flout United Nations Security Council resolutions through attacks on civilians.

"I am grateful for the leadership George Clooney has shown in drawing attention to this crisis - this is a humanitarian tragedy of colossal proportions and the the world must take note and act.

"The UK is working with the international community and others to pressure all sides to agree a ceasefire, start peace talks, and facilitate the rapid deployment of Unamid."

Clooney took up his new UN role in January.

He had just returned from a two-week trip to 19 locations in Sudan's Darfur region, the Central African Republic, Chad and the Democratic Republic of Congo.

"Each conflict zone has difficulties that are unique, but there's always one unifying thread: the worst atrocities are saved for the poorest and most vulnerable," Clooney said previously.

The Oscar winner was selected for his ability to focus public attention on critical international political and social issues.

He took on the job of promoting the world body's peacekeeping missions after waging his own campaigns for an end to the war in Darfur and for more humanitarian aid for the millions caught in the conflict.