Facebook on Monday unveiled new tools to counter online political meddling in the European elections, part of a campaign to answer growing pressure to rein in disinformation.
The US tech giant's vice president, former British deputy prime minister Nick Clegg, said in a speech that the methods would become available in late March and help "make political advertising on Facebook more transparent".
The new rules will require a wide range of political ads linked to the European elections on May 23 to 26 to be specifically authorised and tagged with a clear "paid for by" disclaimer.
Clegg said these tools will also cover so-called issue ads "which don't explicitly back one candidate or political party, but which focus on highly politicised topics like immigration".
Those ads will then be stored on servers for up to seven years, along with the details of their reach and specific data on the buyer of the advertising.
Vera Jourova, the European Union's commissioner for justice and consumer affairs, said Facebook still needed to do more.
"I am glad to hear that Facebook is rolling out new tools and is committed to privacy, but I expect less rhetoric or apologies and more concrete actions, especially when it comes to disinformation and protecting elections from manipulation," Jourova said.
The measures come after a nightmare year for Facebook, marked by a series of scandals over data protection and privacy and concerns that the leading social network had been manipulated by foreign interests for political purposes.
Criticism of Facebook has included allegations that the social network is being used as a platform to spread divisive or misleading information, as was the case during the 2016 election that put US President Donald Trump in the White House.
Facebook ads have also been at the centre of the FBI investigation over Russia's alleged meddling in the US election of Trump and suspicions are rife that the Kremlin has intervened in votes across Europe.
The speech was Clegg's first for Facebook since becoming a big-ticket hire by founder Mark Zuckerberg last year, as the company tries to put the scandals behind it.
Clegg, a former member of the European parliament, said Facebook had turned the page from rejecting tighter government scrutiny and encouraged governments and the EU to lead the way on regulation.
"There is a clear role here for the EU to demonstrate a middle path - a model that combines the dynamism of Silicon Valley with the regulatory rigour of Brussels," Clegg said.
"We would like to be at the heart of that discussion," he said.
Facebook—like Google and Amazon—has been hit with major EU fines in recent years.
Last year the EU's anti-trust authority fined Facebook for providing misleading information about its $19bn takeover of WhatsApp in 2014.
Facebook received closer EU scrutiny after the Cambridge Analytica data scandal and the social network"s role in the dissemination of "fake news".
Last year, Facebook was fined £500,000 by Britain, the maximum possible amount, for a lack of transparency and failing to protect users' information, relating to the scandal.
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