Washington: US President Barack Obama today vowed to "degrade and ultimately destroy" the Islamic State, as he announced a major expansion of the military campaign, including American airstrikes in Syria and the deployment of
475 more military advisers to Iraq, to achieve this goal.

"We will degrade and ultimately destroy ISIL through a comprehensive and sustained counter-terrorism strategy," Obama said in his nationally televised speech in which he set no timeline to achieve his goal to defeat the terrorist group.

"America will lead a broad coalition to roll back this terrorist threat," he said, noting that the US will conduct a systematic campaign of airstrikes against these terrorists.