Executives from Facebook, Google, and Twitter came under fire from lawmakers on three House and Senate Committees last week over how Russia used their platforms to interfere in the 2016 election.

The trio of hearings — from the Senate Judiciary and Intelligence Committees, and the House Intelligence Committee — were highly anticipated after Internet companies started releasing information about the Russia-funded content that made its way into millions of users' Facebook feeds and Twitter timelines, and on YouTube.

The news that users in the U.S. were targeted with content backed by Russian entities raised concerns for lawmakers and watchdog groups, who have since called for legislative and regulatory action.

The Internet companies, too, have taken steps independently in an effort to improve transparency of its paid political ads.

Last month, Facebook announced all paid political ads related to federal U.S. elections will include a disclosure stating “Paid for by.” The company will also create a searchable catalog of all election-related ads, and provide users with information about each one.

According to Facebook’s general counsel Colin Stretch, nearly 150 million Americans across Facebook and Instagram were exposed to content from accounts tied to Russia.

Twitter also said it will label political ads that run on the platform and create a public database of the ads on the platform.

But lawmakers on both sides of the aisle are wary as to whether the proposals from Silicon Valley will meet a standard that’s acceptable to them.

“We’re still kind of digesting what’s being proposed by these recent companies,” Rep. John Sarbanes, D-Md., told the Washington Examiner. “My expectation is that in addition to whatever ad disclosures happen at a granular level, in terms of what hits the user on Facebook or Twitter and their ability to see ads that are running at them, there also needs to be a centralized platform easily accessed by the public that rolls up the ad-buys in a variety of ways that allow people to determine what kind of activity is actually happening.”

Members of Congress have an idea of what their benchmark for transparency of online political ads would look like.

Last month, a bipartisan group of lawmakers in both chambers of Congress introduced legislation requiring Internet companies to create and maintain a public repository of paid political ads running on their platforms.

Called the Honest Ads Act, the bill would require Internet companies to keep copies of political ads, related to both candidates and issues, and make them available to the public. The legislation also requires companies to disclose data related to the ads, including the audience targeted and how much money was spent, and subjects online paid political ads to the same disclosure and disclaimer requirements that apply to radio and TV.

The Honest Ads Act imposes these requirements on websites with at least 50 million monthly viewers or users. Data must be recorded and released for any entity that spends at least $500 per year on political ads.

“To me, this bill is really an update in new technology,” Rep. Mike Coffman, R-Colo., told the Washington Examiner. “We’ve got disclosure requirements for TV and for radio, where I can look up and see who’s buying ads and for how much, but yet we’ve never updated these transparency laws for new technologies such as the Internet. I believe in transparency and updating existing laws.”

Coffman, along with Rep. Derek Kilmer, D-Wash., is a sponsor of the House version of the Honest Ads Act. The Senate’s version is sponsored by Sens. Amy Klobuchar, D-Minn., Mark Warner, D-Va., and John McCain, R-Ariz.

“I hope that people from my party get over the polarization of the Russia issue and how that’s used, and focus on what we’ve always believed as Republicans, in that the more transparency in terms of campaign finance, the more disclosure, in this case, the better,” Coffman said.

Representatives from Facebook, Google and Twitter all told lawmakers last week they take seriously Russia’s use of their platforms and the need to improve transparency of paid politics ads.

And Sarbanes said the Honest Ads Act sets a good standard for lawmakers as they examine the new policies Internet companies roll out.

“We can use that as a benchmark for judging some of the voluntary proposals that are being put forward by these various companies,” he said. “I think it is important that as legislators, we kind of have our radar up that these companies aren’t trying to end-run this conversation and preempt appropriate legislative action that will protect the public’s interest to provide the disclosure and transparency that ought to be in place.”

But neither of the three tech companies that testified last week endorsed the bill.

Stretch said Facebook has “drawn on much of what’s in the bill to inform” its new policies, a statement Twitter’s acting general counsel, Sean Edgett, echoed.

Richard Salgado, Google’s director for information security and law enforcement matters, told lawmakers the company supports “the goals of the legislation,” but would “like to work through the nuances to make it work for all of us.”

Instead, the Internet Association, a trade association that counts Facebook, Twitter, and Google among its members, released a blueprint for legislation and regulations related to online election advertising Tuesday.

“Greater transparency in online election advertising will help to protect the integrity of the U.S. electoral process,” Internet Association CEO Michael Beckerman said in a statement. “Internet Association members are committed to working with policymakers and other stakeholders on legislation that will improve transparency and stop bad actors while protecting privacy, free speech, and Internet-enabled political debate.”

The principles outlined by the group urge lawmakers to ensure the Federal Elections Commission has the authority to regulate and enforce disclosure requirements for online paid political ads and “balance transparency and free speech.”

The Internet Association said it’s in favor of proposals that require platforms to disclose information about political ads to the public, but the organization stopped short of supporting a public repository.

Lawmakers may have to work through disagreements with Internet companies over proposed regulations and legislation, but for Sarbanes, there is an element of haste for both parties.

“It doesn’t help us much if we design and propose the perfect centralized database or if these companies themselves come up with the absolute Cadillac model of what disclosure looks like if it’s not ready and available until two years from now or even right before the election,” he said of the 2018 midterm elections. “They need to move quickly, and Congress needs to move quickly to make sure the remedy we’re looking for here is in place earlier rather than later with respect to this election year, so that by the time people are focusing on getting information and making decisions about candidates and campaigns and the election, they have plenty of information at their fingertips to do that in a responsible way.”