Western supports of the National Coalition for Syrian Revolutionary and Opposition Force, a movement formed last month in Qatar, met for a so-called Friends of Syria meeting in Morocco.
British Foreign Secretary William Hague, whose government was one of the first to recognize the opposition council, said a war-torn Syria needs a new government that can give the people a real alternative to Syrian President Bashar Assad.
Support for the opposition, he said, is needed to start planning for Syria's peaceful future because "we do not know how long the conflict in Syria will last."
Hague said his government was offering more non-military support for Assad's opponents. The Guardian newspaper in London quotes French Foreign Minister Laurent Fabius as saying Paris "shall see in the coming months" whether it should help arm Syrian rebels.
U.S. President Barack Obama told ABC News that his government felt the opposition council was "inclusive enough, is reflective and representative enough of the Syrian population" for formal recognition as the legitimate representation of the Syrian people.
NATO forces had agreed to send Patriot missiles to help Turkey defend its borders against a Syrian civil war slowly engulfing Damascus.
"The people of Syria need to feel the solid ground of a unified political alternative to the Assad regime," said Hague. "The national coalition has now begun to offer that hope."