The US is giving Syrian opposition groups “foreign mission” status to bolster those challenging president Bashar al-Assad as he tightens his already firm military grip over Syria.



The State Department said on Monday the Syrian Opposition Coalition's offices in Washington and New York have been conferred the new, quasi-diplomatic status to shore-up their legitimacy. The group is often referred to interchangeably as the Syrian National Coalition.



US officials said the move was one of several initiatives designed to assist moderate opposition groups in Syria, including provision of $27m in new, non-lethal assistance being negotiated with Congress. That would take the total US assistance to Syrian opposition groups to $278m.



The US has publicly held back from providing the sophisticated weaponry being requested by the Free Syrian Army, which is struggling in its three-year campaign against Assad. A ceasefire deal brokered on Friday facilitated the effective surrender of rebel fighters from the Old City quarter in the strategically important city of Homs.



According to the latest estimates, more than 150,000 people have been killed since the anti-Assad uprising began in March 2011. Geneva peace talks to reach a negotiated settlement in Syria failed, and an emboldened Assad plans to hold stand in a round of presidential elections he has scheduled next month.



A delegation of Syrian opposition figures began arriving Washington over the weekend ahead of intensive meetings with US officials, desperate to put the three-year civil conflict on the agenda of US policymakers.



The head of the Syrian Opposition Coalition, Ahmad Jarba, has said publicly that he intends to persuade Washington to provide advanced weaponry they believe could turn the tide in a conflict they are losing. For months there have been unconfirmed reports that the CIA has been providing a limited supply of weapons to approved, moderate fighters, through backchannels.



The Syrian opposition officials based in the US will not have diplomatic immunity and are not proposing to open an embassy or consulate. In March, the US announced the closure of the Syrian government’s embassy in Washington.



Pressed on the precise benefits of “foreign mission” status, a senior administration official was non-committal, saying only that Syrian opposition officials had requested the special status.



“I don’t want to build this up into something that it isn't,” the official said during a conference call organised by the State Department to promote the announcement. The official declined to speak on the record but did not provide a reason, as is routine for such calls.



Marie Harf, deputy spokeswoman for the department, said later that the status would allow the Syrian opposition group to coordinate “banking and security services”.



“I think it just shows how committed we are to working with the Syrian Opposition Coalition,” she said, “and to say that we believe they are the legitimate representative of the Syrian people.”