Facebook Inc is tightening its political ad rules in the United States, it said on Wednesday, requiring new disclosures for its site and photo-sharing platform Instagram ahead of the US presidential election in November 2020.

The social media giant is introducing a “confirmed organisation” label for US political advertisers who show government-issued credentials to demonstrate their legitimacy.

All advertisers running ads on politics or social issues will also have to post their contact information, even if they are not seeking the official label.

Advertisers must comply by mid-October or risk having their ads cut off.

Under scrutiny from regulators since Russia used social media platforms to meddle in the 2016 US presidential election, Facebook has been rolling out ad transparency tools country by country since last year.

Since May 2018, Facebook has required political advertisers in the United States to put a “paid for by” disclaimer on their ads. But the company said some had used misleading disclaimers or tried to register as organisations which did not exist.

“In 2018, we did see evidence of misuse in these disclaimers and so this is our effort to strengthen the process,” said Sarah Schiff, product manager at Facebook.

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Last year, Vice News journalists managed to place ads on behalf of figures and groups including US Vice President Mike Pence and “Islamic State”. Just last week, Facebook banned conservative news outlet The Epoch Times from advertising on the platform after it used different pages to push pro-Trump ads.

Paid Facebook ads have become a major tool for political campaigns and other organizations to target voters.

President Donald Trump’s re-election campaign has spent about $9.6 million this year on ads on the site, making him the top spender among 2020 candidates, according to Bully Pulpit Interactive, a Democratic firm that tracks digital ad spending.

Last year, Facebook began requiring political advertisers to submit a US mailing address and identity document. Under the new rules, they will also have to supply a phone number, business email and website.

To get a “confirmed organisation” label, advertisers must submit a Federal Election Commission ID number, tax-registered organisation ID number, or government website domain matching an official email.

Facebook has continuously revamped its policies around political advertising, which differ by country.

In 2018, it launched an online library of political ads, although the database has been criticised by researchers for being poorly maintained and failing to provide useful ad targeting information.