BEIRUT — The international envoy working to end Syria’s civil war warned Sunday that the failure of the government and the rebels to pursue a political solution could lead to the ‘‘full collapse of the Syrian state’’ and threaten the world’s security.
Lakhdar Brahimi, who represents the United Nations and the Arab League, said that as many as 100,000 people could be killed in the next year as Syria moves toward ‘‘Somalization’’ and rule by warlords.
Brahimi has reported little progress in his mission to push forward a peace plan for Syria first presented in June at an international conference in Geneva. The proposal calls for an open-ended cease-fire and the formation of a transitional government to run the country until new elections can be held and a new constitution drafted.
But so far, neither the regime of President Bashar Assad nor the scores of rebels groups fighting his forces across the country have shown any interest in negotiations.
Activists reported violence around Syria on Sunday.
Rebels in the north clashed with government troops near military bases in the provinces of Idlib and Aleppo and seized an oil pumping station in al-Raqqa.
The station receives crude oil from the nearby province of Hassakha and pumps it to one of Syria’s two oil refineries in Homs, said Rami Abdul-Rahman, who heads the Syrian Observatory for Human Rights. In recent months, rebels have captured several oil fields in the eastern province of Deir el-Zour that borders Iraq.
The observatory said rebels stormed a government air base in the area of Tel Hassir south of Aleppo, while government fighter jets launched deadly airstrikes near Aleppo, Hama, and in a number of rebellious Damascus suburbs.
Activists also reported two car bombs in the Yarmouk district of Damascus, where most residents are Palestinian refugees.
The rebels’ political leadership has called Assad’s departure a prerequisite for any political solution, and it is unlikely that the opposition’s National Coalition could even stop rebels on the ground from continuing to fight.
Likewise, it is doubtful that top members of Assad’s regime will voluntarily give up power.
The Syrian government has remained officially mum on Brahimi’s plan, which he has pushed in the past week in meetings with Assad in Damascus, with top Russian officials in Moscow and on Sunday with the head of the Arab League in Cairo.
Sergey Lavrov, Russia’s foreign minister, said Saturday that Assad has no intention of stepping down and it would be impossible to try to persuade him otherwise. Lavrov also said that the Syrian opposition risks sacrificing many more lives if it continues to insist on Assad’s leaving office as a precondition for holding talks.
Speaking alongside Nabil Elaraby on Sunday, Brahimi estimated that 100,000 people could be killed if the 21-month conflict continues for another year.
Dire forecast for war-torn nation
‘‘Peace and security in the world will be threatened directly from Syria if there is no solution within the next few months,’’ he said. ‘‘The alternatives are a political solution or the full collapse of the Syrian state.’’
Since meeting Assad early last week, Brahimi has given no indication how his plan was received. When asked Sunday if there is any willingness among the opposition to enter a political process, Brahimi said, ‘‘No, there isn’t. This is the problem.’’
Syria’s crisis began in March 2011 with political protests against Assad. The conflict has since evolved into a civil war. Antiregime activists say more than 45,000 people have been killed.
The Syria government does not give death tolls for the conflict and says the rebels are terrorists backed by foreign powers who seek to destroy the country.
The Syrian conflict has split world powers, with the United States, Turkey, and many European and Arab states calling for Assad to stand down. Russia, China, and Iran have stood by the regime and criticized calls for Assad’s ouster.