Thousands of people have gathered in South Sudan's capital for celebration's marking the new nation's independence.

South Sudan officially became the world's newest country at midnight local time Friday, prompting residents in the capital, Juba, to dance in the streets.

A large crowd has now assembled at a stadium in Juba for the formal declaration of independence.

U.N. Secretary-General Ban Ki-moon is due to attend, along with some 30 African heads of state, including Sudanese President Omar al-Bashir.

Southern Sudan voted overwhelmingly to split from the north in a January referendum. The vote stemmed from a 2005 peace deal that ended more than 20 years of war between north and south Sudan.

Already, South Sudan has been recognized by its northern neighbor. Sudan's minister for presidential affairs, Bakri Hassan Saleh, made the official announcement Friday on state television.

Saturday's ceremonies in Juba will include a proclamation of independence, the raising of the new South Sudanese flag, and the swearing-in of South Sudan's first president, Salva Kiir.

The celebration takes place at the John Garang Mausoleum — named after the leader of southern Sudanese forces during the long civil war. Garang died in a 2005 helicopter crash.

Saturday's festivities belie the challenges the new nation will soon face.

South Sudan is still trying to disentangle itself from Sudan and the two sides have yet to resolve issues on borders and oil revenue. Sudan's army is currently fighting pro-southern Sudan elements in the northern-controlled state of Southern Kordofan.