The US-based Internet backbone provider Cogent Communications has cut off services in Russia, "terminating its contracts" with the customers in the country in compliance with the European Union's move to ban Russian state-backed media outlets.
Unplugging Russia from Cogent's global network will result in slower connectivity, according to a report in The Washington Post.
Cogent routes data across intercontinental connections and is one of the world's largest Internet backbone providers that serves customers in 50 countries, including high-profile Russian companies.
In a letter to Russian customers obtained by The Post, Cogent cited "economic sanctions" and "the increasingly uncertain security situation" as the reason behind its complete shutdown in the country.
However, several digital rights activists criticised Cogent's decision to disconnect itself from Russia, The Verge reported late on Saturday.
"Cutting Russians off from internet access cuts them off from sources of independent news and the ability to organize anti-war protests," Eva Galperin, director of cybersecurity at Electronic Frontier Foundation, posted on Twitter.
Cogent CEO Dave Schaeffer told The Post that its aim is to prevent the Russian government from using the company's networks for cyberattacks and propaganda.
Several parts of Europe were cut off from the Internet after they encountered massive "cyberattacks" at the start of Russia's invasion of Ukraine.
According to reports, the outage was felt in Germany, France, Hungary, Greece, Italy and Poland.
According to telecom company Orange, around 9,000 users of its satellite Internet service were without Internet following a "cyber event" on February 24 at Viasat, a US satellite operator.