WASHINGTON – The government shutdown is hampering America’s ability to maintain pressure on Iran’s nuclear program, a State Department official told a Senate committee Thursday.

Lack of funding and people at work are limiting the activities of the Treasury Department’s Office of Foreign Asset Control and State’s sanctioning monitoring group, two vital elements of checking Iran’s nuclear ambitions, said Under Secretary of State for Political Affairs Wendy Sherman before the Senate Foreign Relations Committee.

Both programs, which oversee sanctions on countries such as Iran and Syria, have been “completely, virtually, utterly depleted,” Sherman said. Intelligence on violations is also suffering due to furloughs at the CIA and NSA, she added.

Sherman pleaded for bipartisan cooperation to end the federal shutdown.

“We believe that we have some time, but we don’t have a lot of time,” Sherman said.

Sherman also faced a series of pointed questions about Iranian President Hassan Rouhani’s “charm offensive” that led to a telephone conversation between Rouhani and President Obama last week.

Obama’s conversation with Rouhani was the first between a U.S. president and an Iranian leader since 1979.

The next steps in the U.S.-Iran engagement are part of a “confidence-building” process that would involve Iran’s revelation of the pace and scope of its nuclear program, Sherman said.

In return, she mentioned the possibility of easing some sanctions imposed because of Iran’s reluctance to comply with the United Nations’ resolution demanding a shutdown of its uranium enrichment program. Sanctions target several sectors of Iran’s economy including its fuel exports.

Senators skeptical of Iran’s motives bristled at the possibility of giving it such leeway.

“The new face of Iran looked and sounded very much like the old face, with a softer tone and a smoother edge,” said Sen. Robert Menendez, a New Jersey Democrat and the committee’s chairman. Even while the committee debated, he said, Iran’s nuclear centrifuges were spinning.

Sen. John McCain, R-Ariz., asked about Rouhani’s questionable record overseeing Iran’s nuclear project before he became president.

“Now, we’re supposed to trust this guy? How much confidence do you have in this individual?” McCain asked.

“I don’t trust the people who sit across the table from me in these negotiations,” Sherman replied. The exchange quickly escalated when McCain interrupted her repeatedly on a timeline for this “test” of Iran’s intentions.

“We enter this period with our eyes open,” Sherman said. She emphasized that the United States would not put anything else on the negotiating table unless Iran “translated its words into transparent, meaningful and verifiable actions.”

Rouhani’s sincerity and intentions should be clearer by mid-October when six countries, including the United States, expect to be sitting opposite Iran at the negotiating table in Geneva, Sherman said. Foreign ministers from the United States, Great Britain, France, Germany, China and Russia are scheduled for full-scale negotiations with Iran about its nuclear program.

Until then, she said, the pressure will be maintained. But the federal shutdown poses a substantial impediment in America’s ability to keep up this pressure, Sherman said.