U.S. to Assad: Beware of interfering with U.S. airpower in Syria

WASHINGTON (Reuters) - The Syrian military's air defences would face retaliation if Syria attempted to respond to U.S. airstrikes that are expected against Islamic State targets in Syria, senior U.S. officials said on Monday.

President Barack Obama's authorization of the use of American airpower against Islamic State's strongholds in Syria has raised the question of whether Syrian President Bashar al-Assad would respond in some way.