Sheikh Mohammed bin Zayed, Crown Prince of Abu Dhabi and Deputy Supreme Commander of the Armed Forces, and US Secretary of Defence James Mattis have discussed tackling terrorism and extremism during a phone call, state news agency WAM reported on Sunday. The two leaders discussed ways to strengthen friendship and cooperation between the UAE and the United States, particularly in military and defence affairs. Sheikh Mohammed and Mr Mattis touched on the latest regional and international developments, as well as joint cooperation to enhance regional security to fight extremism and terrorism.