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.

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.

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 Chief of Defence Forces (CDF) also first son Gen Muhoozi Kainerugaba has said that Uganda has deployed special forces in South Sudan’s capital Juba to “secure it” as tensions between President Salva Kiir and his First Vice President Riek Machar stoke fears of a return to civil war.

South Sudan, the world’s youngest country, has been repeatedly consumed by deadly feuding among politicians and militia leaders since its independence from Sudan in 2011. An estimated 400,000 people died in prolonged fighting in the oil-rich African country from 2013 to 2018.

South Sudan declined on Wednesday to confirm the deployment of Ugandan troops amid rising political and military tensions, raising fears of a potential escalation between rival factions and a return to full-scale conflict.

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.