As political pressure mounts on social media companies to say where ads are coming from, Twitter will reveal more information about political advertising on its platform.

Twitter said in a blog post on Tuesday it would clearly label political electioneering ads, which the Federal Election Commission (FEC) defines as an ad used to promote a specific candidate for elected office or affiliated party posted within 30 days of a primary election or 60 days of a general election. Electioneering ads can also include any ad clearly promoting a political candidate at any time.

The ads will have some sort of visual marker, likely a purple dot next to the user handle, and a purple box with the text “Promoted by” andthe name of the sponsor.

In addition, the company will limit which criteria can be used to target people, and will introduce a “stronger” penalty on those who do not abide by the new rules. The company did not say what the tougher standards or penalties will be.

Twitter, along with Facebook and Google, are sending their lawyers to Congress to testify as lawmakers investigate Russian involvement in the 2016 election through online political ad buying. Lawmakers from both sides of the aisle have introduced the “Honest Ads Act” as a way to get platforms to disclose more about paid online political ads. The legislation would require platforms with 50 million or more monthly unique visitors to have a public database of political ads and records for anyone who bought more than $500 worth of political ads in the previous 12 months.

Twitter’s move to provide more information on political ads lines up with most of what Congress is asking for.

The company will also launch a “transparency center,” which will show all ads — political or not — currently running on Twitter, and how long the ads have been running. The database will show users which ads have been targeted toward them and the personal criteria used to target them.

Political ads specifically will have additional information in the center, including all associated campaign ads currently running or that have run on the platform. It will show who funded the campaign, how much they spent on this specific campaign, and how much they spent on the platform in total. There will be information on the criteria used to place the ad, like age, gender and geography.

The new ad policies will be first be enforced in the U.S., but will expand globally eventually.