BEIRUT (AP) — Syria’s main Western-backed opposition bloc urged the European Union to quickly supply rebels fighting President Bashar Assad’s forces with sophisticated weapons as activist groups inside the country accused the opposition leadership today of failing to fulfill its obligations to the Syrian people.

The Revolutionary Movement in Syria, an umbrella organization of activist groups from across the country, threatened to withdraw its backing for the Syrian National Coalition if the notoriously fractured opposition leadership in exile doesn’t come up with a strategy that will represent millions of Syrians caught up in the country’s bloody civil war. While the loss of support would have little practical effect, it would deal a sharp symbolic blow to the coalition, which has long been accused of being out of touch with those on the ground in Syria.

The coalition has been meeting for days in Istanbul, but has failed to agree on several key points, including on whether to attend international peace talks in Geneva with representatives of Assad’s regime aimed at finding a resolution to the more than 2-year-old conflict.

The Revolutionary Movement said the coalition is “unable to fulfill its obligations due to the ongoing discord” among its different parties and said the statement today was its “last warning” before they withdraw their support.

“We have waited in vain for many months for the National Coalition to take concrete steps, and offered its leadership multiple chances to do so,” the statement said. “The reality is that there is no doubt that the … leadership has failed to fulfill its responsibility to represent the great Syrian people’s revolution at the organizational, political, and humanitarian levels.”

The opposition coalition has yet to decide whether to attend the U.S.-Russia sponsored peace talks. The deeply divided umbrella group that is backed by the United States and its European allies insists Assad must relinquish power before any talks with Damascus can take place.

Damascus previously said that it would “in principle” attend the Geneva talks.

The Geneva talks, though seen as a long shot, are the international community’s only plan for ending the conflict that has killed more than 70,000 people and force more than five million people from their homes to seek refuge in neighboring countries and in other parts of Syria.

Meanwhile, the coalition urged the European Union to quickly supply rebels fighting Assad’s forces with sophisticated weapons to help them overthrow his regime.