South Sudan President Salva Kiir has dissolved the transitional government, three months before the country's first election since its independence in 2011.

The country has previously postponed elections twice and extended the transitional period several times.

Under the amended law, signed on Monday, Kiir removed the country's five vice-presidents and dissolved parliament, as well as national and state governments.

Kiir is the presidential candidate of his Sudan People's Liberation Movement (SPLM). No prominent figures have announced plans to challenge him in the December poll. The main opposition leader Riek Machar was sacked as vice-president last year and charged with treason.

He is under house arrest.

Machar had been named vice-president as part of a 2018 peace deal to end a five-year civil war between forces loyal to the two men.

Kiir will remain in office with full constitutional powers until an elected president is sworn in. He also reappointed some ministers and governors in caretaker positions until the 22 December elections.

Ahead of Tuesday's announcement a heavy security presence was reported in the capital, Juba. Soldiers from the army and national security services blocked access to government ministries. Soldiers were also seen patrolling parts of the city.

A senior government official told the BBC that staff arriving for work were turned away and told to return the following Monday.

UN agencies in Juba also asked staff to work remotely while the situation was monitored.

Kiir last week dismissed the chairman of the national elections commission, Abednego Akok Kacuol, without giving a reason. He was replaced by the commission's secretary-general, Gabriel Bol Deng.

Akok had said in August that the commission needed $250m (£190m) to conduct the election but had received only $21m.

In June, the main opposition group, the Sudan People's Liberation Movement in Opposition (SPLM-IO), the party of Machar, warned people not to take part in poll preparations.

"Anyone coming to register voters and campaign in territories controlled by the mighty SPLM-IO, you will be a prisoner of war," Nathaniel Pierino, acting chairperson of the group, said in a post on Facebook.

The body which oversees implementation of the 2018 peace agreement, the Reconstituted Joint Monitoring and Evaluation Commission (RJMEC), said South Sudan had entered a "critical phase".

It said several key talks under the agreement remained incomplete and urged the parties to agree on a path towards credible elections and a peaceful end to the transitional period, which has lasted since independence.

The latest 24-month extension was due to end on 22 February 2027.

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