"[The Russia-US cooperation] exists and continues to develop", Kulyagin told reporters.
According to the official, Russia considers cooperation with the US security services as important as cooperation with agencies of other countries.
Following the revelation, Democratic Senator Chuck Schumer called on intelligence leaders in a letter to explain these meetings given their own assessment that Russia interfered in the 2016 election.
READ MORE: Under Siege: CIA Chief Says Cooperation With Russia Is Critical for US Security
CIA Director Mike Pompeo hit back in a letter of his own, telling Schumer that there was nothing "untoward" about US and Russian intelligence officials meeting.
Such cooperation is critical to national security and puts less American lives at risk, the CIA head said, adding that Moscow and Washington collaborated on aviation security and on preventing foreign fighters from going back to both Russia and the United States.