The Russian telecom regulator said Tuesday that it will retaliate against Google if the search giant lowers the search ranking of the Kremlin-backed news outlets RT and Sputnik, escalating a tense back and forth over Russian news coverage that has entangled American news bureaus abroad and could lead Moscow to enact further censorship rules.

The agency’s remarks come after Eric Schmidt, the executive chairman of Google's parent company, Alphabet, said that the company would de-rank the two Russian media outlets in its search results. Speaking at the Halifax International Security Forum over the weekend, Schmidt said Google is working to curb misleading and exploitative content, as well as material that is likely to have been “weaponized” for nefarious purposes.

When asked why Russian-backed sites enjoy favorable placement on Google's platforms, Schmidt said, “We are working on detecting this kind of scenario … de-ranking those kinds of sites. It’s basically RT and Sputnik are the two." He added that the company does not want to ban the outlets. And according to Google, the company does not re-rank individual websites.

The Russian regulatory agency on Tuesday did not take kindly to Schmidt’s comments, saying it intended to push back if it discovers that Google is acting in an “unfriendly” way. Alexander Zharov, head of the agency, Roskomnadzor, said it would ask Google to explain the concept of ranking as it is applied to RT and Sputnik. “We'll hope that our opinion will be heard and we won't have to resort to more serious measures,” Zharov said, according to the Interfax news agency.

Later, a spokesman for Roskomnadzor said that it had sent Google a note demanding an explanation, and said that it was drafting “retaliatory measures” in case it decides that RT and Sputnik are being treated unfairly.

Margarita Simonyan, the editor of RT, made it clear that she considers Google’s actions discriminatory. “If that’s not censorship, I don’t know what is,” she told Russian television. Simonyan has denied the conclusion by U.S. intelligence agencies in January that RT and Sputnik, along with a network of “quasi-government trolls,” interfered on the Kremlin’s behalf in the 2016 election by peddling anti-American propaganda.

Google declined to comment, but referred The Washington Post to a company blog post from April outlining changes to its search results.

Google isn't the first global technology company to take recent action against Russian-affiliated media. Last month, Twitter announced that RT and Sputnik would be barred from buying advertisements on its platform. The company said it based its decision on the U.S. intelligence assessment that the outlets acted as propaganda tools.

Google search ranking is just the latest battlefield where a brewing dispute between the U.S. and Russian governments is playing out. Russian lawmakers unanimously passed a bill earlier this month that would allow authorities to force any foreign media organization to register as a “foreign agent” after RT was forced to register under a similar statute in the United States. Russian President Vladi­mir Putin is likely to sign the measure into law by the end of the month.