Uganda has deployed special forces in South Sudan's capital Juba to "secure it", Uganda's military chief said on Tuesday, but South Sudan's information minister denied the presence of troops, as tensions between South Sudan's president and first vice president stoke fears of a return to war.

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 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.

"We shall protect the entire territory of South Sudan like it was our own," he added on the social media platform X. South Sudan's government has not yet commented on the deployment. Concern about the security situation in South Sudan has been mounting,

The arrests in Juba and deadly clashes around the northern town of Nasir are seen as jeopardizing 2018 peace deal that ended a five-year civil war