Qatar is committed to defeating the Islamic State, its emir, Sheikh Tamim Bin Hamad al-Thani, assured U.S. President Barack Obama on Tuesday in his first official visit to the White House.

Obama said the emir committed to fighting Islamic extremists and supporting the moderate opposition in Syria.

Qatar is part of the U.S.-led coalition fighting the Islamic State, which controls a wide swath of territory in Syria and Iraq.

The two leaders are "deeply concerned" about the situation in Syria and shared ideas on how they can transition Syrian President Bashar al-Assad out of power, Obama told reporters in the Oval Office.

"We'll continue to support the moderate opposition there, and continue to believe that it will not be possible to fully stabilize that country until Mr. Assad, who has lost legitimacy in the country, is transitioned out," Obama said. "How we get there obviously is a source of extraordinary challenge, and we shared ideas in terms of how that can be accomplished."

In the past, there has been suspicion that money has gone from Qatar to violent extremist groups in the region.

The emir said Obama told him he was committed to a peace process between Israel and Palestinians.

"I'm happy to learn and to hear from you, President, that you are committed to find this peace process in Palestine," he said to Obama in front of reporters in the Oval Office.