According to a story by the South China Morning Post, the popular Chinese social media app was blocked by the country's telecom watchdog Roskomnadzor for failing to register with the relevant authorities.
Tencent's spokesman Zhang Jun in response said the company is in contact with Russian authorites regarding the issue.
"We're experiencing a block and we're deeply sorry", a company official said on a Tencent microblog.
Internet-based companies which have links in Russian Federation are required to register with the government.
A law passed in 2014 requires foreign messaging services, search engines and social networking sites to store the personal data of Russian users inside Russia.
Earlier a similarly worded reason was named when Zello, Line and Blackberry messengers got blocked in Russian Federation.
Meanwhile social media applications such as Facebook and Twitter are blocked in China, with President Xi Jinping a vocal advocate of so-called cyber sovereignty.
With over 800 million users worldwide, the block of WeChat within Russian Federation has already triggered widespread complaints among Chinese citizens living there and others who use the app for daily life and work.
The authorities took action after the company failed to discharge the various responsibilities regarding information distribution on the internet, the newspaper stated.