U.S. State Department spokesman Ned Price told reporters that "we obviously welcome this as a positive step".
The parties to the Irannuclear deal will meet in Vienna on Tuesday as efforts are revving up to bring the United States back into the agreement.
US officials will also be in Vienna for consultations but so far are not expected to be part of the larger meeting.
Agreement on the start of multiparty talks - being held to get Iran and the United States over their differences on conditions for returning to the 2015 nuclear deal - came after talks Thursday brokered by other countries in the accord. "The path ahead of the U.S.is fully clear".
The commission will meet relevant experts to "to clearly identify sanctions lifting and nuclear implementation measures". "In this context, the coordinator will also intensify separate contacts in Vienna with all JCPOA participants and the United States".
"We've been looking at options for doing so, including with indirect conversations through our European partners", Price added.
USA will take part in a meeting in Vienna next week on the Iran nuclear deal.
In last month's interview with the U.S. news outlet Politico, Zarif reiterated Iran's readiness to adhere to the JCPOA "as soon as the United States comes to compliance".
In a tweet, Zarif said the aim of the Vienna session would be "rapidly finalize sanction-lifting & nuclear measures for choreographed removal of all sanctions, followed by Iran ceasing remedial measures".
The U.S. and Iran have been in a standoff over reviving the nuclear deal.
Zarif tweeted that Tehran plans to hold an in-person meeting with the remaining signatories to the JCPOA, namely, representatives of the EU, France, Germany, the UK, China, and Russian Federation in Vienna on 6 April.
Russia's ambassador to global organizations in Vienna, Mikhail Ulyanov, tweeted that Friday's session went well and the parties were prepared to talk further.
The online meeting will be chaired by the deputy secretary general and political director of the European External Action Service (EEAS) Enrique Mora on behalf of EU High Representative Josep Borrell.
The ultimate goal of the deal is to prevent Iran from developing a nuclear bomb, something it insists it doesn't want to do.
Earlier this month, Iranian supreme leader Ayatollah Ali Khamenei said his country may return to full compliance of the JCPOA if Tehran deems Washington has honoured its commitments.