Damascus, Sep 23 (IANS): Washington had informed Syria of airstrikes against positions of the Islamic State (IS) in Syria before these strikes started, the Syrian foreign ministry said in a statement Tuesday.

The statement said that Syria's envoy to the UN was informed Monday about the commencement of the US-led airstrikes against IS positions in Syria's northern province of al-Raqqa, adding the airstrikes started before daybreak Tuesday, Xinhua reported.

The ministry did not mention the Syrian government's response to the airstrikes.

The opposition Syrian Observatory for Human Rights said the US launched 20 airstrikes in al-Raqqa and its surroundings region.

Abu Muhammad al-Raqqawi, a Syrian activist, told foreign media that the first strike targeted the al-Tabaqa military air base, which had been captured by the IS recently.

Other activists said dozens of IS fighters were either killed or injured in the strikes.

Washington and its partners have begun striking IS targets in Syria with a mix of fighters, bombers and Tomahawk missiles, according to the Pentagon.

Arab nations like Bahrain, Saudi Arabia, Jordan and the United Arab Emirates participated in the airstrikes with Qatar playing a supporting role, BBC reported.

The strikes were expected as part of President Barack Obama's pledge to degrade and destroy IS, who have taken control of large swathes of territory in Iraq and Syria.

The US has already launched 190 airstrikes in Iraq since August.

Pentagon spokesman John Kirby confirmed the strikes, saying US military and partner nation forces were undertaking military action in Syria, but he refused to give details.

"Given that these operations are ongoing, we are not in a position to provide additional details at this time," he said in a statement.