Should be pointed out that the U.S. State Dept. did this on Tues.:

U.S. Criticizes Iran’s Role in Syria Ahead of Peace Talks
Uskowi on Iran, Jan. 7, 2014

The U.S. today questioned Iran’s seriousness in wanting to put an end to the nearly three-year-old Syrian civil war, accusing it of helping the Assad regime to brutalize its people.

“At this point, Iran has done nothing but helped the [Assad] regime… If they wanted to send a message to the world about their seriousness of having a positive outcome, there are steps they could take. There’s no indication that they have any desire or interest in taking any of these steps,” said Jen Psaki, State Department spokeswoman. (AP, 7 January)

but it also should be noted that that was within the context of whether they should be invited to the peace conference on Syria:

Secretary of State John Kerry is scheduled to meet with his Russian counterpart Sergey Lavrov next week to determine whether or not an invitation will be extended to the Islamic Republic to Geneva II peace conference, which is to open January 22 in Montreux, Switzerland.

White House Calls New Sanctions on Iran A Call for Military Action
By Nader Uskowi, Uskowi on Iran, Jan. 10, 2014

 

The White House on Thursday challenged a group of senators seeking news sanctions on Iran to admit they are working to push the U.S. toward military action.

 

“If certain members of Congress want the United States to take military action, they should be up front with the American public and say so,” Bernadette Meehan, National Security Council spokeswoman, said in a statement.

 

“Otherwise, it’s not clear why any member of Congress would support a bill that possibly closes the door on diplomacy and makes it more likely that the United States will have to choose between military options or allowing Iran’s nuclear program to proceed.” (HuffingtonPost, 9 January)

 

The Foreign Relations Committee Chairman Bob Menendez is pushing legislation, backed by a majority of the Senate, that would tighten sanctions on Iran in apparent violation of the 24 November Geneva accord signed by Iran and P5+1.

Iran, P5+1 Negotiators Resolve ‘All Remaining Issues’
Agreement Reached Sent to Capitals for Final Approval
By Nader Uskowi, Uskowi on Iran, Jan. 10, 2014

Iran’s deputy FM and senior nuclear negotiator Abbas Araqchi told Iranian state television from Geneva that the two-day talks produced “good results” and the two sides did reach agreements on “all remaining issues” over how to implement the 24 November nuclear deal. He added, however, that due to political sensitivities surrounding some of the agreements reached, the two sides decided to refer final approval of the agreements to their capitals.

 “We have resolved all remaining issues. But due to (political) sensitivities of some of the resolutions, it was decided to refer them to (respective) capitals for final approval,” Araqchi said. (IRIB, 10 January)

Araqchi said the agreements reached today in Geneva will be announced publicly in a day or two after the final approval by the countries’ capitals. He added that the two sides still hope to begin the implementation of the accord on 20 January.