U.S. Secretary of State John Kerry and Syrian Opposition Council President Khaled Khoja met Thursday to discuss Syria's ongoing crisis and ways to boost U.S. assistance to the opposition."The situation on the ground in Syria and in the communities around it is simply unsustainable, catastrophic," Kerry told reporters before meeting with Khoja at the State Department. "It has a profound impact – negative - on each of the surrounding communities, particularly Lebanon, Turkey, and Jordan, but especially on the people of Syria."Syria's four-year conflict has displaced roughly three quarters of the country, with about half of those fleeing to Syria's neighbors, according to Kerry.In remarks translated from Arabic, Khoja said he would discuss the establishment of safe havens in areas of Syria that have fallen under opposition control during his meeting with America's top diplomat."President [Bashar] Assad has no legitimacy and he is not part of the future of Syria. And for that reason he needs to be prosecuted and subjected to a fair trial for the crimes he has committed against the Syrian people," Khoja said.During their meeting Kerry reaffirmed Washington's commitment to a political transition in the war-torn nation, and stressed that Assad's government cannot be part of the future of the country, according to State Department spokeswoman Marie Harf."The secretary underscored the Assad regime's continued crimes and atrocities against the Syrian people, including the use of barrel bombs and chemical weapons, have aided and abetted a magnet for extremists in Syria," she said.