Uganda has deployed an unknown number of troops to South Sudan in a bid to protect the fragile government of President Salva Kiir as a tense rivalry with his deputy threatens a return to civil war in the east African nation.

South Sudan's government has denied earlier reports that Uganda had deployed special forces to its capital, Juba. Uganda's military chief Gen Muhoozi Kainerugaba said the soldiers had gone to the neighbouring country to help South Sudanese President Salva Kiir "secure" the city.

The situation in South Sudan is fragile and getting worse, with growing political and military instability. The claims made by the information minister do not reflect the reality on the ground.

The leadership of the United People’s Alliance (UPA) has condemned the decision by the Government of South Sudan to invite the Uganda People’s Defence Forces (UPDF) to South Sudan amid tensions and conflicts in Upper Nile, Western Bhar Ghazal and Western Equatoria states.

Tension mounts in South Sudan as power deal between President Salva Kiir and Vice President Riek Machar unravels.

Ugandan special forces have been deployed to South Sudan's capital Juba, the Ugandan army chief said Tuesday, after rising tensions threatened a fragile peace agreement between President Salva Kiir and Vice President Riek Machar.