Updated

Voter registration began in Southern Sudan on Monday in preparation for a January independence referendum that could see Africa's largest country split in two.

Voters lined up at more than 2,600 registration centers around the country. In the capital, Juba, Southern Sudan President Salva Kiir showed off an ink-stained finger after registering.

Most observers expect the south to vote for independence, an outcome even the U.S. government has labeled "inevitable."

In the elementary school in the Nile River town of Melut, a gathering of young voters lined up to register said they hope to help create a new country.

"We are going to vote for separation. All of us," said 20-year-old Deng Juach, who showed off his laminated registration card to friends.

The registration process had been delayed by political disputes between Sudan's ruling party in the north, the National Congress Party, and the south's Sudan People's Liberation Movement.

The two parties signed a 2005 peace deal that ended a two-decade civil war. The deal promised a referendum on independence for Southern Sudan in January 2011 and a separate self-determination vote for Abyei, a disputed border zone.

Northern Sudan is mainly Muslim, while the south is mainly Christian and animist. The separate region of Darfur, in Sudan's west, would remain a part of the Khartoum-based north.

"Unity is not good. We want separation," said Gieth Kon Awlan, 18. "It is good for all of us. ... We have no problem with Darfur, but there is a big problem with Khartoum."

Chan Reec Madut, deputy chairman of the Southern Sudan Referendum Commission, described the mood in Juba as "jubilant." He said he spoke to would-be voters who complained of long lines to register.

"I told them, 'You waited 15 years, why not wait a few more hours?'" Madut said.

Registration for the Jan. 9 vote will last for 17 days, after which an objections and appeals process begins. A final list of voters will be published Jan. 4.

Preparations for the separate Abyei vote have not begun due to an ongoing disagreement between the two political parties over who is eligible to vote. Protracted negotiations mediated by President Barack Obama's envoy to Sudan and by former South African President Thabo Mbeki have not yet succeeded in reaching an agreement.

The latest round of north-south talks last weekend, though, did reach some agreement. A statement from the African Union issued Monday said the two parties agreed to maintain a "soft border" if the south votes to secede.

The statement said a soft border would allow pastoral communities to move back and forth over the border and to make cross-border trade easier. The statement said the soft border is essential for economic prosperity and harmony between the north and south.

Southern Sudan is one of the poorest regions of the world. Some 85 percent of southerners cannot read or write, so educating voters is a challenge.

The referendum commission announced over the weekend the symbols that will appear on January's ballot: Unity will be represented by a picture of two hands clasped together. Secession will be signified by one hand.