Observers note Kislyak is a somewhat unlikely figure to cause controversy. Over the course of a long diplomatic career, he’s led the life of a somewhat typical global envoy – making himself a reliable presence on the circuit of receptions, teas and forums that make up the calendar of any ambassador.

Kislyak, who was appointed to his post in 2008, is regularly spotted walking around town, heading to and from meetings. Early in his tenure, he often opened the doors of the Russian Embassy, hosting dinners for foreign policy professionals, Pentagon officials, journalists and Capitol Hill staffers.

Those who have attended the events describe him as a gracious and amiable diplomat, although perhaps not as polished – nor as confrontational – as his more famous boss, Foreign Minister Sergey Lavrov.

In 2015, when Kislyak invited a group of Washington-based journalists, including one from the Associated Press, to the Russian Embassy for tea, he used the meeting to push warmer relations between the two nations – despite the conflict over Russia’s seizure of Crimea and the crisis in Ukraine.

Kislyak framed US-Russian relations as salvageable and hoped specifically to combat what he considered cartoonish, anti-Russian depictions of his government in the American press.

At a press conference where he recused himself from the investigation into the Trump campaign’s ties with Russia, Sessions said he discussed a number of things with Kislyak, including counterterrorism. He said the meeting became confrontational when the discussion turned to Ukraine.

Kislyak, 66, has bounced between the United States and Russia for most of his long career.

His first foreign posting was to New York where he worked at the Soviet delegation at the United Nations in the early 1980s. He spent the following years as the first secretary and then councillor at the Soviet Embassy in Washington before returning to Moscow in 1989, where he took a succession of senior jobs at the Foreign Ministry.

He did a stint as Russian ambassador to Belgium and simultaneously served as Moscow’s envoy at Nato. He then returned to Moscow to serve as a deputy foreign minister, overseeing relations with the United States and arms control issues before being sent to Washington.

Kislyak’s contacts have sparked questions about his role or involvement in the hacking, questions that are difficult to answer.

Kislyak denied that Russia was meddling in the election during an address to the Detroit Economic Club less than two weeks before the November 8 election.

“We have become kind of collateral damage in the fight between the two parties,” he said, adding that Russia is “ready to work with any president that is going to be elected.”

Opinions differ on whether Kislyak is a spy in the American sense of the word.

“For them it’s much grayer,” Steven Hall, former head of Russia operations at the CIA, said of the Russian view of the difference between a diplomat and spy. “I would say [Kislyak] is most definitely both. In the Russian system, it’s simply assumed that they’re all collecting and doing whatever they can either covertly or overtly.”

The US and Russia, along with many other countries, have made it a practise to separate their top diplomats from espionage activities, although it is not uncommon for an intelligence agent to operate under the cover of a senior-level diplomat. Foreign diplomats to the United States likely expect that their activities will be monitored by US authorities in the same manner that American diplomats are monitored in countries like Russia.

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Russian ambassadors most likely are aware of the intelligence agents operating under diplomatic cover, but are not believed to part of the security services themselves.

Russian Foreign Ministry spokeswoman Maria Zakharova on Thursday ridiculed the claims of Kislyak’s involvement in espionage as “total disinformation” and part of efforts to sway public opinion.

“I’ll open a military secret for you: it’s the diplomats’ jobs to have contacts in the country they are posted to,” she said sarcastically. “It’s their obligation to meet with officials and members of the political establishment.”

Additional reporting by The Washington Post