ISTANBUL (REUTERS) - Syria's opposition coalition said on Tuesday that President Bashar al-Assad's forces had dropped phosphorus bombs and napalm on civilians in rural Aleppo on Monday, killing at least 10 people and wounding dozens.

The alleged attack occurred as the United States and its European and Middle Eastern partners honed plans to punish Mr Assad for a major poison gas attack last week on the suburbs of the capital Damascus that killed hundreds of civilians.

Video footage uploaded on the Internet, apparently of Monday's attack, showed doctors frantically smearing white cream on the reddened skin of several screaming people, many of them young boys.

"Assad's military aircraft have hit populated areas with the internationally prohibited phosphorus bombs and napalm," the opposition coalition said in a statement.

It was not possible to independently confirm the report.

There have been previous unconfirmed reports of the use of phosphorus bombs by Mr Assad's forces during Syria's conflict, now in its third year.