A stalemate that had been in place for four years ended in July 2016, when Syrian government troops closed the last supply line of the armed opposition into Aleppo with the support of Russian airstrikes. In response, rebel forces launched unsuccessful counteroffensives in September and October that failed to break the siege; in November, government forces embarked on a decisive campaign. The rebels agreed to evacuate from their remaining areas in December 2016. The Syrian government victory was widely seen as a potential turning point in Syria's civil war.