Russia's notoriously rigid government media watchdog has warned newspapers and news sites around the country: Should you publish Charlie Hebdo cartoons, prepare to be blacklisted.

The warning was issued via letter to the offices of several media outlets, including editorial department of a local Kamchatka editor, who published the text of it on Facebook.

"Please be informed of the position of Roskomnadzor concerning the terrorist attack on January 7, 2015 in Paris," the letter begins. It goes on to state that the "inclusion in any media of caricatures of the religious leaders is unacceptable; placing online media links to other media materials (including foreign), copyright material justifying these events, caricatures of religious figures will be considered as a violation of Roskomnadzor Federal Law 'On Countering Extremist Activity.'"

The letter is signed Maria Vladimirovna Smetankina, acting head of department for protection of human subjects, personal data, supervision of mass communications and information technology for Roskomnadzor in the Kamchatka territory. Smetankina could not be reached for comment Tuesday, and a Roskomnadzor official declined to speak further about the letter, but confirmed its authenticity by phone to Mashable.

"This is our official position," the official said.

Smetankina appeared to play down the letter, explaining to Russia's RBK news service that Roskomnadzor's was not issuing a warning to media, but that the law should be respected.

Pavel Chikov, chairman of Agora, a Russia human rights organization, tweeted that his group was ready to provide legal assistance free of charge if "a journalist or media, for any cartoons, authorities bring any claim."

Если журналисту или СМИ за какие-либо карикатуры власти предъявят какие-либо претензии, Агора готова обеспечить правовую защиту. Бесплатно — Pavel Chikov (@pchikov) January 13, 2015

Roskomnadzor's letter, reportedly sent to media officers on Monday, comes as satirical French magazine Charlie Hebdo readies its first issue after the deadly attack on its offices in Paris last Wednesday, which 12 dead. French newspaper Liberation, which is helping to print the issue, released a photo of what will be one the front cover.

It features a cartoon of the Prophet Muhammad shedding a tear and holding a "Je Suis Charlie" sign. Above the cartoon, is the message: "All is forgiven." The magazine will print 3 million copies instead of its usual 60,000.

In Russia, Tuesday also marked the Day of Russian Journalists. Roskomnadzor, while sending out warning notices to media offices, also wished journalists a good day, albeit with a caveat, on Twitter.

"Congratulations to all the reporters and editors on the Day of Russian press!" the Russian watchdog organization wrote. "Do not forget about the observance of Russian laws."