Russian authorities have charged two former officers in the Federal Security Service and an employee of cyber security firm Kaspersky Lab with committing treason in the interests of the United States, a lawyer representing one of the three said.

Pavlov identified the three as Kaspersky employee Ruslan Stoyanov and FSB officers who specialized in cyber security, Sergei Mikhailov and Dmitry Dokuchayev.

"My client, along with the others, has been charged with state treason and cooperating with U.S. intelligence services," Pavlov told Reuters in a telephone interview.

He declined to say which of the three he was representing, saying only that Stoyanov was not his client.