Washington, Dec 18 (IANS): The US Tuesday ordered its non-emergency personnel to leave South Sudan, voicing deep concern about the worsening situation in the country.

The State Department "ordered the departure of non-emergency US government personnel from South Sudan because of ongoing political and social unrest," Xinhua reported.

American nationals have also been warned against "all travel" to South Sudan.

"The circumstances there have gotten worse, and we remain deeply concerned about developments in South Sudan," White House spokesperson Jay Carney told reporters at a regular news briefing.

Clashes renewed Tuesday in South Sudan's capital of Juba, as authorities were making wide-ranging arrests targeting senior political leaders following an attempted coup a day earlier.

South Sudan's President Salva Kiir Monday declared a state of emergency in the country and imposed a curfew from 6 p.m. to 6 a.m. after the failed coup which he said was launched by soldiers loyal to his former deputy Riek Machar.

"We're deeply troubled by the fighting that continues today in Juba," State Department spokesperson Marie Harf said at a regular press briefing.

"We encourage the country's political leaders to refrain from any action that could further escalate an already tense situation and urge them to calm their supporters."

She refused to characterise what was unfolding in South Sudan, saying, "At this point it's still premature to say what sparked the violence."

South Sudan won independence from Sudan in July 2011.