Congo Republic's ruling party on Monday officially designated incumbent President Denis Sassou Nguesso as its candidate for a March election, bringing the veteran leader one step closer to extending his decades-long rule, according to Reuters. Sassou Nguesso has ruled the oil-rich Congo for 31 of the past 36 years in two separate stretches. He is widely expected to win a comfortable victory in the polls, having secured the right to seek a third consecutive term in a constitutional referendum last year. The decision to back his candidacy, generally viewed as little more than a formality, was taken by members of the central committee of Sassou Nguesso's Congolese Party of Labour (PCT). Opposition parties boycotted October's constitutional referendum, during which security forces placed some party leaders under house arrest and fired on anti-government protesters, killing at least four people. While they have conditionally agreed to participate in the election, many observers expect at least some of them to pull out ahead of the March 20 poll date.