A 4000-strong East African military unit that the United Nations Security Council recently authorised for South Sudan is designed as a “protection,” not an “intervention,” force, UN diplomats said on Friday.

The assurances were offered at a news conference in Juba as a Security Council delegation started a four-day visit to the turbulent country.

Jointly led by the United States and Senegal, the UN representatives “really want to move the ball” toward peace and stability in South Sudan, said US Ambassador Samantha Power.

Her co-leader, Ambassador Fodé Seck of Senegal, emphasised that the Security Council resolution calling for additional troops to be deployed in Juba was based on respect for South Sudan's sovereignty.

Alluding to Africa's rejection of colonialism, Ambassador Seck said “national sovereignty is paramount for all our countries.”

That history has led proponents of the regional deployment to avoid calling it an intervention force, the Senegalese envoy noted.

“The word 'intervention' in Africa rings very, very unpleasant bells,” Ambassador Seck said. “So this is a protection force. That’s why the resolution has been adopted unanimously.”

The Security Council's three African members — Angola, Egypt and Senegal — voted for the resolution last month, as did the council's 12 other members.

Ms Power said she agreed with her Senegalese colleague, noting that “references to the force as an intervention brigade may have left a bad taste in some folks’ mouths.”

The council delegation is seeking to clarify the force's role, the US envoy added.

The United Nations does use the term “intervention” for a 3000-member combat-equipped brigade authorised in 2013 to fight rebel groups in the eastern Democratic Republic of Congo.

The Security Council acted to enhance the UN's military mission in South Sudan following clashes in Juba in July that killed scores of civilians.

Sexual assaults on South Sudanese women and international aid providers also took place at that time.

“We have a lot of questions about how those attacks can have occurred and why there has been no visible accountability for the perpetrators of those attacks," Ms Power told reporters prior to the council delegation's meetings with South Sudan government officials.