Russian President Vladimir Putin said the foreign intelligence service was exceptionally important for protecting the country, in comments made soon after it was accused by some of being behind a major hack on U.S. government departments.

Speaking at an event commemorating 100 years since the founding of the SVR foreign intelligence service, Putin said the agency and other security services were a crucial guarantee of Russia’s “sovereign, democratic, independent development.”

Some international cyber researchers have suggested that Russia’s SVR foreign intelligence service may have been behind an unprecedented attack on U.S. government computer systems first reported by Reuters last week.

U.S. Secretary of State Mike Pompeo said on Friday that Russia was responsible for the attack. The Kremlin has always denied Moscow’s involvement in cyber attacks against the West. It has said that Russia had nothing to do with this latest assault.

Putin told attendees of the event, which also marked the Day of the Security Services Worker, that it was important to continue developing the work of counterintelligence agencies.

“I know what I’m talking about here,” Putin, a former KGB agent, said, in comments shared on the Kremlin website. “And I rate very highly the difficult professional operations that have been conducted.”

“The most serious attention must be paid to information security, to the fight against extremism and against corruption,” he added.

He also told members of the agency to pay particular attention to risks posed by conflicts “simmering” near the country’s borders.

Clashes have again been reported between Armenia and Azerbaijan over the Nagorno-Karabakh enclave despite a Russian-brokered ceasefire. Weekly anti-government protests continue in Belarus.

“I expect that the Foreign Intelligence Service will continue to respond flexibly to the highly changeable international context, actively participating in identifying and neutralising potential threats to Russia, and improving the quality of its analytical materials,” Putin said.