Mokdad acknowledged that by aligning themselves with Jabhat al-Nusra, the other rebel factions could jeopardize hopes of receiving outside military help, just as the Obama administration says it is starting to step up its support after more than a year of hesitation.But, he said, the United States and its allies are to blame, for failing repeatedly to deliver on promises to provide assistance as the death toll in Syria, now well over 100,000, steadily mounted. The development appeared to take the Obama administration by surprise. A senior State Department official, briefing reporters Tuesday night on a meeting at the United Nations between Secretary of State John F. Kerry and Syrian Opposition Coalition Chairman Ahmad al-Jarba, was unaware of the rebel announcement that had been made several hours earlier.In a statement Wednesday, State Department spokeswoman Jen Psaki said that officials had “seen the reports” and were “discussing with the moderate opposition what impact this will have going forward.”“A divided opposition benefits the Assad regime and opportunists who are using the conflict to further their own extreme agenda,” Psaki said. U.S. aid would continue, she said, “taking into account that alliances and associations often change on the ground based on resources and needs of the moment.”