ZAGREB - US Secretary of State Hillary Clinton has warned the Syrian opposition of what she described as attempts by Islamists to hijack the revolution against the regime of President Bashar Al-Assad.
"There are disturbing reports of extremists going into Syria attempting to take over what has been a legitimate revolution against an oppressive regime for their own purposes," Clinton told reporters during a visit to Croatia, Agence France-Presse (AFP) reported.
The opposition should "strongly resist the efforts by the extremists to hijack the Syrian revolution", she said.
More than 36,000 people have been killed in Syria's 19-month revolution against Assad's regime.
The revolt against Assad began as peaceful protests calling for democracy and greater rights, but gradually turned to an armed struggle, pitting the Sunni majority against the president and his minority Alawite sect.
Clinton said it was important the successors of Assad should be committed to rejecting extremism.
"There needs to be an opposition that can speak to every segment and every geographic part of Syria, she said.
And we also need an opposition that will be on record strongly resisting the efforts by extremists to hijack the Syrian revolution.
Despite calling for Assad's departure, Washington has been reluctant to arm the Syrian opposition, worried of the growing rule of Islamists in the uprising against Assad.
US President Barack Obama's administration has said it is limiting its aid to the opposition to non-lethal humanitarian assistance.
It concedes, however, that some of its allies are providing lethal assistance - a fact that Assad's chief backer Russia says shows western powers are intent on determining Syria's future.
Russia and China have blocked three UN Security Council resolutions aimed at increasing pressure on the Assad government, leading the United States and its allies to say they could move beyond UN structures for their next steps.
Clinton has also called for an overhaul of the Syria's opposition leadership to help accelerate Assad's fall.
"There has to be a representation of those who are on the front line fighting and dying today," she said.
The Paris-based Syrian opposition umbrella is primarily made up of opponents to Assad in exile.
The Free Syrian Army, the umbrella rebel group fighting in Syria, has accused the opposition of seeking to make political gains without consulting with those fighting on the ground.
Divisions have also surfaced among the fighting rebel groups, as many fighter leaders have accused the FSA head of lacking legitimacy over his residence in Turkey while his fighters were dying inside the country.
The belated move by Riad al-Asaad back into Syria last month has done little to change their stance.
Clinton said a meeting will be held next week in Qatar to look into means of broaden the opposition to include parties fighting on the ground in Syria.
"We are working very hard with many different elements of opposition inside and outside Syria," she said, adding that the United States was interested in "helping the opposition to unite strongly and resist the Assad regime".Washington wanted to assist the opposition "to unite behind a shared effective strategy that can resist the regime violence and begin to provide for a political transition".