Mark Zuckerberg, Facebook’s founder and CEO, said Friday that he supports legislation sponsored by Sen. Amy Klobuchar, D-Minn., that would regulate online political ads.

“Election interference is a problem that’s bigger than any one platform, and that’s why we support the Honest Ads Act,” Zuckerberg wrote in a Facebook post. “This will help raise the bar for all political advertising online.”

He is scheduled to testify next week before Congress in the wake of the company’s admission that data firm Cambridge Analytica improperly gained access to up to 87 million users’ data.

Facebook’s support for the bill “is a sign that they realize the public mind-set is changing on this,” Klobuchar said Friday. “They are going to have to now come before Congress … and explain how they’re going to protect people’s privacy.”

Zuckerberg also said Friday that every advertiser who sponsors an issue ad, which don’t support individual candidates, will have to “confirm their identity and location.” Facebook already requires the identity and location of political ad buyers.

Zuckerberg will testify Tuesday at a joint session of the U.S. Senate Judiciary and Commerce committees. Klobuchar serves on both. On Wednesday, he will appear before a House panel.

The Honest Ads Act was introduced in October in response to concerns about Russian meddling in the 2016 presidential campaign.

Sponsored by Klobuchar, Sen. Mark Warner, D-Va., and Sen. John McCain, R-Ariz., it would require internet companies to ensure that ads are not purchased by foreign individuals and entities to influence American voters. It would require digital with 50 million or more monthly views to publicly disclose how much ads cost and how they are targeted.

Facebook competitors Google and Twitter have not endorsed the legislation. Klobuchar said Facebook’s support improves chances of the measure’s passage.

“The big argument against it was, oh, it’s so burdensome,” she said, an assertion that could now be more difficult to make.