Moscow has been highly critical of actions by the Syrian armed opposition, even while expressing support for a political solution. The listing of al-Nusra Front as a foreign terror organization is a step that Moscow could welcome.

U.S. recognition of the opposition could anger Moscow but it also could have a positive effect. Russia has warned that chaos could ensue if al-Assad is deposed. The United States could use this recognition as a signal to Russia that the opposition council is moving toward becoming a viable government should al-Assad leave.

The next steps in dealing with the Syrian opposition leadership depend to a large extent on how that opposition continues to develop.

Nuland pointed to the process of recognizing the opposition in Libya as a template.

Recognition is just part of the process of trying to create a political solution for the Syrian conflict. At the same time, the United States is trying to urge Russia to use its influence with Damascus to help bring about a political solution.

That was the focus of recent meetings between the two countries facilitated by the joint special representative of the United Nations and Arab League for Syria, Lakhdar Brahimi.

In a statement, Brahimi said the diplomats "explored avenues to move forward a peaceful process and mobilize greater international action in favor of a political solution."

Nuland said on Monday the question now is whether there are figures in the opposition who could come together.

"Perhaps there are folks who are currently in the government without blood on their hands who could support those kinds of democratic principles and form the basis of a transitional structure going forward," Nuland said.

"Mr. Brahimi thinks it is worth a try," she added. "We want to support his efforts and we'll have to see where that goes."