Obama: working to establish facts on Syria chemical weapons use

US President Barack Obama said on Monday the United States would keep increasing pressure on Syrian President Bashar Assad to stop the "appalling violence" in Syria, and was still investigating the reported use of chemical weapons there.

"We will continue to work to establish the facts around the use of chemical weapons in Syria and those facts will help guide our next steps," Obama told a joint news conference at the White House with British Prime Minister David Cameron. (Reuters)