Mark Zuckerberg on Wednesday launched into a lengthy defense of the platform’s policy against moderating or fact-checking political ad content, declaring that Facebook (FB) should err on the side of defending “free expressions” in a turbulent environment.

In the wake of Twitter CEO Jack Dorsey’s abrupt decision to ban all political advertisements, Zuckerberg used the company’s third quarter earnings call to issue a statement of what he called Facebook’s “principles” in the face of widespread criticism about fact-checking ads.

Zuckerberg articulated several reasons why the platform should resist the “urge” to ban political speech, defending free speech with few restrictions. He called political ads an important tool for politicians to get their message across, “and it’s hard to define where to draw the line” on moderating such content.

“I view the role of this company as defending free expressions,” the CEO said, saying society needs to be “careful about adopting more and more rules that restrict what people can say. In a democracy, I don’t think it’s right for companies to censor politicians or the news.”

Facebook has come under intense fire over its refusal to fact-check political ads, which drew heat recently from the presidential campaign of Democrat Elizabeth Warren. The company has found itself in the crosshairs of Congress, dozens of State Attorneys General and virtually everyone in between.

Some critics have argued Facebook is profiting from false advertisements, but Zuckerberg stated that political ads amount to less than a percent of the platform’s total revenue in that category. He also enumerated several ways in which Facebook screens content while promoted free speech as a core principle.

“While we may disagree on specific issues,...voice and expression have been important throughout our history,” Zuckerberg said on Wednesday. “Our company will continue standing for these principles.”

The CEO’s stance has put him at odds with his own employees, who recently wrote an open letter calling its laissez-faire policy on political ads “a threat to what Facebook stands for.” In announcing Twitter’s ban, Dorsey took a clear jab at his Facebook counterpart in a lengthy thread.

“For instance, it‘s not credible for us to say: “We’re working hard to stop people from gaming our systems to spread misleading info, [but] if someone pays us to target and force people to see their political ad…well...they can say whatever they want,” Dorsey wrote in one post — adding a wink emoji at the end.