Russia has introduced tougher internet laws in the last five years, requiring companies to store Russian users' personal data on servers within the country, search engines to delete some search results, and messaging services to share encryption keys with security services.

Yuri Kontemirov, acting deputy head of the watchdog, was quoted by Interfax news agency as saying the checks would be completed in the second half of February.

(Reporting by Gabrielle Tétrault-Farber and Maria Kolomychenko; writing by Tom Balmforth; editing by Maria Kiselyova)