Updated

Russia's foreign minister says it is essential "to prevent the destruction" of the U.S-Russia cease-fire agreement for Syria.

Sergey Lavrov told the U.N. General Assembly on Friday that it was vital to support U.N. resolutions calling for an end to the fighting in Syria and for a political settlement.

Lavrov said there must be "an unbiased and impartial investigation" of airstrikes that killed Syrian soldiers in Deir el-Zour and bombings in and around the northern city of Aleppo.

Lavrov said the Syria conflict cannot be resolved "without the suppression" of the Islamic State group and al-Qaida-linked fighters.