US urges South Sudan President Kiir to release VP Machar from 'house arrest'

The US on Thursday called on South Sudan President Salva Kiir to release his rival First Vice-President Riek Machar who his party says is under house arrest, as the UN warned the country was on the brink of civil war.

Machar's SPLM-IO party said on Wednesday that the defence minister and chief of national security "forcefully entered" Machar's residence and delivered an arrest warrant.

Machar was being held with his wife at his home, accused of supporting the White Army militia which clashed with the military in Nasir, Upper Nile state, this month, Reath Muoch Tang, a senior SPLM-IO official said in a statement.

Under a peace deal which ended a 2013-2018 civil war between forces loyal to Machar on one side and Kiir on the other, the two men have been serving in a fragile coalition government.

"We are concerned by reports South Sudan's First Vice-President Machar is under house arrest," Washington's Bureau of African Affairs wrote on X. "We urge President Kiir to reverse this action & prevent further escalation of the situation."

South Sudan's army and government spokespeople did not immediately respond to requests for comment about Machar.

In the capital, Juba, the army was heavily deployed near Machar's house, some shops were closed and there was less traffic than normal on Thursday morning, a Reuters journalist said.

The UN has warned that recent violence in Nasir involving the White Army, a militia with historical ties to Machar, and a rise in hate speech could reignite along ethnic lines the civil war.

Machar's SPLM-IO party denies ongoing links with the White Army.

"It is time for South Sudan's leaders to demonstrate sincerity of stated commitments to peace," Washington's Bureau of African Affairs wrote on X.

Political analysts say Kiir has been attempting to shore up his position by rounding up some of Machar's most senior allies, inviting Uganda's army to secure the capital and naming adviser Benjamin Bol Mel as second vice president. They say Kiir, 73, is preparing Bol Mel, a businessman designated on the United States' sanctions list for his links to construction firms accused of money-laundering, to succeed him.

The UN peacekeeping mission in South Sudan (UNMISS) called for restraint on Thursday, saying the country stood on the brink of relapsing into widespread conflict. "This will not only devastate South Sudan but also affect the entire region," UNMISS said in a statement.

The five-year civil war, which was fought largely along ethnic lines, resulted in hundreds of thousands of deaths in the world's youngest nation.

On Wednesday the UN reported fighting between forces loyal to Kiir and Machar close to Juba.