Libya moved closer to a first World Cup appearance after defeating Togo 2-0 in Tripoli Friday.
The Mediterranean Knights have nine points from five games in Group I — three more than Cameroon — with a September fixture in Yaounde to come.
Cameroon are away to the Democratic Republic of Congo Sunday and their chances of making the play-offs would greatly diminish if they lose.
Libya have nine points, Cameroon six, DR Congo five and Togo are out of the running with four as only group winners advance to the 10-team final stage.
Faisal Saleh converted a penalty on seven minutes amid tight security at the Tripoli Stadium and Komlan Amewou conceded an own goal not long after.
It was a pleasing improvement by the Libyans, whose captain Ahmed Osman had a penalty saved last weekend in a 0-0 draw with DR Congo at the same ground.
Togo were reluctant visitors to Libya after demonstators and militia clashed in second city Benghazi last weekend, leaving 31 dead and 100 wounded.
France-based Alaixys Romao and Jonathan Ayite pulled out of the trip, but Serge Gakpe changed his mind and was in the starting line-up.
Libya came closest to qualifying for the World Cup in 1985 when beaten 3-1 by Morocco on aggregate in the final elimination round.
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