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Talks urged in South Sudan conflict as US Marines deployed

Tony Karumba / AFP - Getty Images

People gather at a makeshift IDP camp at the United Nations Mission in South Sudan compound in Juba on Dec. 22, 2013 where South Sudanese continue to flock as fears of a resumption of fighting in the capital fester.

WASHINGTON — The U.S. special envoy to South Sudan pushed to get warring sides in a deepening conflict to the negotiating table — even as the Pentagon moved 150 Marines to a base in the Horn of Africa to prepare for possible evacuations. 

In a conference call with reporters, Donald Booth said his discussion with South Sudan President Salva Kiir was “frank and open,” and that Kiir would be open to talks without preconditions “as soon as his counterpart was willing.” 

After a weekend mission to retrieve Americans is thwarted, marines now are scheduled to get dozens of Americans out of a very tense Sudan. NBC's Andrea Mitchell reports.

But former Vice President Riek Machar, a member of a rival ethnic group who was dismissed from the South Sudanese government in July, has previously said he would not negotiate unless Kiir releases Machar's detained political allies, according to Reuters. 

A senior administration official on the call acknowledged that “there are a lot of details as to how” the two leaders “will be brought together: Where they will be brought together, what it is they will be willing to discuss” -- which he said Booth will be in charge of working out.  

Violence broke out on Dec. 15 in the country’s capital, Juba, and Kiir, from the Dinka ethnic group, blamed Machar, a rival Nuer, for instigating violence and staging a coup. Machar suggested that these claims may, in fact, be warranted, telling the BBC on Saturday that rebel troops spreading from Juba to key oil-producing areas were under his control. 

The U.S. has evacuated about 380 Americans and 300 third-country citizens from South Sudan since last week, when the fighting began. Conducting airlifts from the region has proven difficult — U.S. aircraft had to abort an airlift mission in Bor, the site of the latest violence, on Saturday after three Osprey helicopter-airplane hybrids were fired at.

Hakim George / Reuters

South Sudan's President Salva Kiir addresses a news conference at the Presidential Palace in capital Juba Dec. 16, 2013.

The U.S. and United Nations were able to evacuate Americans on Sunday after “discussions with rebel commanders,” who allowed the evacuations to proceed, according to the official on the call.

The United States and United Nations have both committed resources geared toward keeping Americans and other civilians in the region safe. The Pentagon moved 150 Marines from their base in Spain to the country of Djbouti on Monday to be on call for deployment to South Sudan for security or evacuation missions. 

United Nations Secretary-General Ban Ki-moon said Monday that he would recommend to the U.N. Security Council an increase in peacekeepers in the world's youngest country to protect civilians. Reuters reported there are already about 6,800 peacekeeping troops and 700 police in South Sudan, which was declared a sovereign state in July 2011. 

The official on the conference call said no decision has been made as to whether the U.S. would suspend any aid to South Sudan, which mostly consists of humanitarian assistance, until the fighting stops. 

NBC News' Courtney Kube contributed to this report.