George Clooney, the Hollywood actor who spends increasing amounts of his spare time playing the role of a globe-trotting peace activist, has hardly been able to contain his excitement over this week’s controversial referendum on splitting Sudan in two.

“It is something to see people actually voting for their freedom,” the Ocean’s Eleven star gushed as he mingled with the long queues of tribesfolk patiently waiting to cast their votes. “That’s not something you see often in life.”

The 49-year-old was speaking as an estimated four million voters in southern Sudan, predominantly Christians, took part in a plebiscite that will decide whether the south is divided from the north to form a new nation.

When the polling stations close on Saturday, it is widely predicted that the pro-independence campaign will get the 60 per cent of the vote needed to sanction the division of Africa’s largest country – which is equivalent in size to Germany, France, Italy, Poland, Spain, Greece and the UK combined.

The referendum is being held as part of a peace deal agreed in 2005 between the government of President Omar al-Bashir and the leaders of southern Sudan’s rebel movement, after more than 20 years of bitter civil war, which claimed an estimated two million lives.