"We are well aware that Facebook has a significant number of users on the territory of the Russian Federation. On the other hand, we understand that this is not a unique service, there are other social networks," said the head of Russia's internet watchdog Roscomnadzor Aleksandr Zharov in an interview with the Interfax news agency.

According to Zharov, Facebook's position is that it "continues to consider" options for complying with the Russian law, which obliges internet companies to store personal data of Russian users on servers inside Russia.

"There have been no official letters from them," Zharov said, adding that Facebook can repeat the fate of LinkedIn, which was blocked in November last year.

"In any case, we will either ensure that the law is implemented, or the company will stop working in the territory of the Russian Federation, as, unfortunately, happened with LinkedIn. There are no exceptions," Zharov said.

Many companies including Viber, eBay, and others complied and moved or started moving servers containing personal data to Russia. LinkedIn refused to comply with the law and was banned in November last year.

Zharov said Facebook will be checked to see if it is complying with the law in 2018.

Other companies are cooperating with the Russian government, according to Zharov, pointing out Twitter, which plans to transfer personal data by mid-2018.

"We will give Twitter some slack because the company wrote us an official letter. Twitter won't be checked now, but immediately after the set date," he said.