US President Barack Obama welcomed a UK parliamentary vote authorising air strikes against DAESH in Syria during a phone call with British Prime David Cameron on Friday.
British fighter jets launched their first air strikes against DAESH in war torn Syria on Thursday, after a parliamentary vote on Wednesday, following over 10 hours of discussions that resulted in 397 British lawmakers voting in favour of the strikes and 223 against.
Obama "expressed his appreciation that British air forces have joined with ours and those of other coalition members in striking ISIL [DAESH] in Syria as well as in Iraq," the White House said in a statement.
During their phone call, Obama and Cameron discussed what extra steps might be taken to degrade DAESH, according to the White House.
They also "reiterated that all countries are welcome to join the existing coalition, if their political and military objectives in Syria are consistent with those of the coalition."
Russia continues to conduct an independent air campaign in Syria which it claims is targeting DAESH.
The US-led coalition said Moscow is supporting Bashar al-Assad and targeting mostly opposition forces rather than DAESH targets.
:They also discussed ways to further bolster our already robust counterterrorism cooperation, and the president, on behalf of the American people, accepted the prime minister's condolences for the loss of life in the San Bernardino shootings this week," the White House said.
US Federal Bureau of Investigation said on Friday that a mass shooting at an office party in San Bernardino, east of Los Angeles, California, which killed 14 people was being investigated as an "act of terrorism."