Syria's military has launched its toughest offensive yet to keep rebel forces out of the capital, activists have said, as the opposition rejected an offer by Russia to host talks with the government.

Monday's diplomatic effort comes as the UN Security Council discusses a resolution to end months of bloodshed in Syria.
Meanwhile, opposition activists in Syria are becoming more daring. Amateur video posted online appears to show two young men unfurling the green, white and black Syrian pre-independence flag, on a bridge in the heart of the capital Damascus.

This was the nation's flag prior to the 1963 coup, and is now being used to represent the current revolution.

Al Jazeera's Dorsa Jabbari reports.