South Sudan army soldiers hold their weapons as they ride on a truck in Bor, 108 miles northwest from the capital Juba, on Dec. 25, 2013. James Akena/Reuters

South Sudan's government has committed to an immediate ceasefire, the country's regional neighbors said on Friday, as they urged rebel leader and the former vice president, Riek Machar, to make the same commitment.

Regional heads of state who attended a meeting of east African body Inter Governmental Authority on Development in the Kenyan capital Nairobi, said they want all the warring parties in South Sudan to meet for talks by Dec. 31.

The authority "welcomes the commitment by the government of Republic of South Sudan to an immediate cessation of hostilities and calls upon Dr. Riek Machar and other parties to make similar commitments," the group said in a statement.

Meanwhile, government forces were successful in defeating South Sudanese fighters loyal to Machar in Malakal, the capital of South Sudan’s major oil producing region.

"(Government forces) are 100 percent in control of Malakal town and are pursuing the forces of the coup," army spokesman Philip Aguer told Reuters in Juba, the capital of South Sudan. On Thursday, Aguer said rebels controlled half of Malakal.

But despite the proposed ceasefire and control of Malakal, it’s unclear whether the violence in South Sudan, which started when President Salva Kiir accused his former vice president of orchestrating a coup, is any closer to ending.

So far, the fighting has caused the displacement of more than 120,000 people across the country, according to the United Nations.

The ceasefire statement came as African leaders met again in Kenya at a summit focused on South Sudan. They hope to produce a roadmap for peace talks.

South Sudan negotiated a split from Sudan in 2011 after decades of a brutal war of independence fought against Sudan. The young country has been plagued by corruption, ethnic tension, and a power struggle within the ruling party between Kiir and Machar.

Machar, the alleged leader of renegade forces now in control of some parts of South Sudan, remains a fugitive wanted by the military. At least 10 of his political allies are in detention for their roles in the alleged coup plot. Machar denies there was a coup attempt, and some officials with the ruling party insist violence broke out when presidential guards from Kiir's majority Dinka tribe tried to disarm guards from the Nuer ethnic group, to which Machar belongs, leading to wider military clashes along ethnic lines.

The number of internally displaced people continues to rise, with many seeking shelter at U.N. compounds across the country. There are continued sporadic military clashes in the oil-rich states of Unity and Upper Nile, potentially endangering the oil revenues that South Sudan depends on to keep the government running.

The U.N. said aid agencies need at least $166 million to save lives.

The top U.N. humanitarian official in South Sudan, Toby Lanzer, said earlier this week that he believes the death toll has surpassed 1,000. The U.N. also is investigating alleged mass killings in the latest violence.

"We have heard reports of extrajudicial killings, arbitrary detentions of civilians, ill-treatment, abuse and also mass graves," said Hilde Johnson, head of the U.N. mission in South Sudan. "Our human rights officers have been working around the clock, throughout this crisis, and they are investigating these reports and allegations."

U.N. Secretary-General Ban Ki-moon has repeatedly urged South Sudan's leaders to start talks, but it remains unclear when Kiir and Machar will start negotiations.

Machar, an influential politician who appears to command the loyalty of Nuer army officers, has criticized Kiir as a dictator and says he will contest the 2015 presidential election. Kiir had fired Machar as his deputy in July following a power struggle within the ruling party, stoking ethnic tensions in a country with a history of divided military loyalties.

Al Jazeera and wire services