Washington is providing both "lethal and non-lethal" support to members of the Syrian opposition, U.S. National Security Adviser Susan Rice said on Friday, according to Saudi-owned TV channel al-Arabiya.

Rice gave more details than are usually provided by Obama administration officials, who usually decline to specify the type of support provided to the moderate Syrian opposition forces.

Rice, who was speaking to CNN while traveling with President Barack Obama to the 70th anniversary celebrations of D-Day in Normandy, said the United States "has been the single largest contributor of humanitarian assistance, providing over $1.7 billion dollars.”

She said that the U.S. had "ramped up its support for the moderate, vetted opposition, providing lethal and non-lethal support where we can to support both the civilian opposition and the military opposition."

Rice's words echoed those of Obama, who said that the U.S. would "ramp up" support for rebels fighting President Bashar Assad during a major foreign policy speech last week.

Caitlin Hayden, Rice's spokeswoman, later declined to say whether Rice's openness on U.S. assistance reflected a new policy initiative.

"We're not in a position to detail all of our assistance, but as we've made clear, we provide both military and non-military assistance to the opposition," Hayden said.

Rice also told CNN that the U.S. was working with Syria’s neighbors to help alleviate the refugee situation, as well as to confront the threat of terrorism seeping out of Syria.

“We're working on the counterterrorism challenge because as we have seen there are increasingly emanating from Syria the threat of terrorism to the neighbors and beyond,” she said.

“Our efforts are increasing and why we'll remain very much engaged, both in trying to support the Syrian people and trying to support the Syrian opposition,” she said.