A top Russian intelligence official was able to travel to the U.S. for high-level meetings last week despite being targeted by sanctions that typically prohibit such visits.
The official -- Sergei Naryshkin, the head of the Russian Foreign Intelligence Service -- met with his American counterparts to discuss the fight against terrorism, Russian Ambassador to the U.S. Anatoly Antonov told Russian state TV.
The visit came less than a week before President Donald Trump decided not to issue any new sanctions against Russian politicians and oligarchs over Russian meddling in the U.S. election.
Senate Minority Leader Chuck Schumer, D-N.Y., a frequent critic of Trump's treatment of Russian President Vladimir Putin and his government, said the timing of the trip was suspicious.
"This is a serious national security issue," Schumer told reporters. "Russia hacked our elections. We sanctioned the head of their foreign intelligence, and then the Trump administration invites him to waltz through our front door. This is an extreme dereliction of duty by President Trump, who seems more intent on undermining the rule of law in this country than standing up to Putin."
Schumer wants to know whether sanctions were discussed, whether Naryshkin also met with White House or national security officials and whether other sanctioned Russian officials were along on the trip. Naryshkin was sanctioned in 2014 in response to Russia's annexation of Crimea.
The U.S. ambassador to Russia, Jon Huntsman, told a Russian radio station on Tuesday that CIA Director Mike Pompeo recently met with Russian spy officials, but he did not say where the meeting occurred or say specifically who attended. Huntsman was underscoring cooperation between the two nations.
"Just in the last week, he (Pompeo) has had probably the most important meetings on counterterrorism that we've had in a very, very long time, at the senior levels," Huntsman said in the interview with the radio station Echo of Moscow.
The CIA released a statement saying that while it does not discuss the schedules of U.S. intelligence leaders, "rest assured that any interaction with foreign intelligence agencies would have been conducted in accordance with U.S. law and in consultation with appropriate departments and agencies."
Jonathan Schanzer, a sanctions expert at the Foundation for the Defense of Democracies, told the Associated Press that typically people who have been sanctioned have their assets frozen and are barred from entering the United States. He said there are cases where individuals from sanctioned countries enter the United States after getting permission to attend meetings at the United Nations.
Situations like Naryshkin's visit are more unusual, Schanzer said.
"We don't see this sort of thing being reported very often," he said.
The Associated Press contributed to this report.