Sen. Dianne Feinstein, a top member of the minority party in the upper chamber, met recently with Iranian Foreign Minister Mohammad Javad Zarif at a time of escalating tensions between Washington and Tehran.

The two had dinner around the end of last month when Zarif was visiting the U.S., sources told Politico.

Feinstein's team said the dinner was designed to update the senator on the situation between the U.S. and Iran and was "arranged in consultation with the State Department." A State Department official said the agency did not ask the California Democrat to meet with Zarif, but did not deny discussions had taken place.

Feinstein is a member of the Senate Intelligence Committee and was formerly the chairwoman and vice chairwoman of the panel. Zarif was an architect of the Iran nuclear deal, an agreement struck during the Obama administration that placed restrictions on Tehran's nuclear weapons program in exchange for sanctions relief. After taking office, President Trump announced the U.S. would withdraw from the deal and reimposed sanctions.

Zarif was also one of the Iranian officials who met with former Secretary of State John Kerry about salvaging the Iran nuclear deal. This led to accusations by the Trump administration that Kerry violated the Logan Act, a more than 200-year-old law that prohibits unauthorized private citizens from acting on behalf of the U.S. in disputes with foreign governments but has never been used to prosecute anyone.

U.S.-Iran relations began to worsen last month after the Trump administration decided not to issue waivers for countries to import oil from the Islamic Republic and sweeping sanctions on Iran’s metal industries, ratcheting up what Trump calls a "maximum pressure" campaign against the rogue regime. The Trump administration also designated Iran’s Revolutionary Guard a foreign terrorist organization, escalating tensions in the region and leading Iran to label the entire U.S. military as “terrorists.”

In recent weeks, officials claimed to have intelligence of an increased threat level against U.S. forces in the Middle East and Navy deployed a carrier strike group and B-52 bombers to the region. Adding to the tensions, a preliminary U.S. analysis found Iran was behind a recent attack on two Saudi oil tankers.

Further complicating matters, the head of Iran's Atomic Energy Organization claimed the regime can restart production of highly enriched uranium in just four days as Iranian President Hassan Rouhani announced his country will not comply with parts of the nuclear deal.

Key congressional Democrats suggested that Trump’s administration was preparing for military conflict with the regime based on faulty intelligence or even false pretenses after ambiguous U.S. warnings that Iranian proxies might attack American personnel in Iraq. Secretary of State Mike Pompeo and acting Defense Secretary Patrick Shanahan briefed the House and Senate on the intelligence that prompted the deployment to the Persian Gulf but appeared to have done little to allay Democrats' suspicions.

During a visit to Iraq on Sunday, Zarif said Iran will not bow to U.S. pressure. “We will defend against any war efforts against Iran, whether it be an economic war or a military one, and we will face these efforts with strength,” Zarif said.

Trump struck a different tone during a news conference in Japan on Monday, saying, “I really believe that Iran would like to make a deal, and I think that's very smart of them, and I think that's a possibility to happen." He also denied the U.S. is looking for regime change in Tehran, but rather wants to ensure the Iranian regime does not obtain nuclear weapons.