Updated

The deeply divided United Nations Security Council has failed to approve a statement calling on Syria to facilitate immediate access to 2,500 civilians trapped in Homs, where pro-regime troops have launched a major offensive to oust rebel fighters.

Russia, Syria's closest ally, and Western nations, which support the opposition, were again at odds — as they have been since the Syrian conflict began over two years ago.

Russia's U.N. Mission said it proposed an alternative statement calling for immediate access to Homs as well as the predominantly Shiite government-controlled towns of Nubul and Zahra, which the opposition is seeking to take.

U.N. diplomats, speaking on condition of anonymity because negotiations were private, said Russia rejected compromise language calling for access "to reach civilians in Homs and all areas of ongoing hostilities."