The Republic of Congo's main ruling party on Friday officially named President Denis Sassou Nguesso, a 36-year veteran of power, as its candidate for upcoming elections, a senior party member said.

"The Central Committee of the PCT (Congolese Party of Labour) unanimously approved the appointment of Comrade Denis Sassou Nguesso as the PCT's candidate," said Esther Ayissou Gayama, a member of the party's central committee.

Sassou Nguesso, 77, has cumulatively spent 36 years in power since he first became president in 1979, making him one of the longest-serving leaders in the world.

In 2015, the country staged a referendum on removing a 70-year age limit and a ban on presidents serving more than two terms.

The move paved the way for Sassou Nguesso to secure a third term in elections in March 2016 that were marred by bloodshed and claims of fraud.

The decision by the PCT leadership, made after a two-day meeting, formally endorsed a decision by the party congress in December 2019.

The PCT is the biggest party in a coalition of 17 groups which also backed his candidacy on December 10.

Sassou Nguesso has yet to make an announcement.

Elections must be held by March 21.

Other contestants who have declared their hands are Guy-Brice Parfait Kolelas, 60, who was runner-up in 2016, and Mathias Dzon, 73, a former finance minister.

In 2016, two candidates who disputed the results, former general Jean-Marie Michel Mokoko and former minister Andre Okombi Salissa, were arrested, tried and handed 20-year jail terms on charges of undermining state security.

The Republic of Congo, a former French colony also called Congo-Brazzaville, is an oil-rich but also poverty-stricken smaller neighbour of the Democratic Republic of Congo.

The country is in the grip of a deep economic crisis, triggered by the slump in oil prices but worsened by long-standing debt and the impact of the coronavirus pandemic.

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