Google News is limiting the reach of two Russian media outlets, RT and Sputnik, according to Alphabet executive chairman Eric Schmidt.

On Saturday, Schmidt said Google is "de-ranking" sites it claims have been spreading Russian state-sponsored propaganda. "It's basically RT and Sputnik are the two," Schmidt said at the Halifax International Security Forum. "We're well aware of it, and we're trying to engineer the systems to prevent it."

Schmidt made the remark when a forum attendee said one of his Google Alerts had largely been serving him news articles from Sputnik, which US intelligence has accused of peddling propaganda for the Russian government. According to the forum attendee, the Sputnik articles were also using Google's ad platform to generate revenue. (Video of Schmidt's talk is embedded below; his session starts at the 1:06 mark.)

"We are well aware of this one," Schmidt said in response. "We are working on detecting this kind of scenario you are describing and de-ranking those kind of sites."

However, Schmidt was quick to add: ""We don't want to ban the sites. That's not how we operate."

Nevertheless, RT and Sputnik denounced Schmidt's statement.

"Good to have Google on record as defying all logic and reason: facts aren't allowed if they come from RT, 'because Russia,'" said Margarita Simonyan, the editor-in-chief of both news outlets.

Last month, Twitter also took action against the two media outlets; it decided to ban ads from RT and Sputnik for their suspected role in helping the Russian government spread propaganda in last year's US presidential election.

On Saturday, Alphabet's chairman said he isn't in favor of censorship, but his company also has a responsibility to stop the misinformation. "We started with a position — the American general view — that bad speech will be replaced by good speech," Schmidt said.

However, well-funded opponents have shown they can quickly spread misinformation online before Google can act. In response, the search company has been developing new features and computer algorithms to detect factually wrong articles, and show news stories from more authoritative sources. Unfortunately, they haven't always worked.

Schmidt said the attempts to spread misinformation will become automated. The actors behind them are also learning ways to circumvent Google's safeguards. "I don't think the problems will go away," he said. "Because I think the people who seek to manipulate will get better tools too. In that sense, it's a race."