WASHINGTON • Manipulated videos of House Speaker Nancy Pelosi that made it seem as if she were stumbling over and slurring her words continued to spread across social media, fuelled by US President Donald Trump's feud with the Democratic Party leader.

One of the videos, which showed Ms Pelosi speaking at a conference, appeared to be slowed down to make her speech sound continually garbled. The video has been viewed millions of times on Facebook and was amplified by the President's personal lawyer, Mr Rudy Giuliani, who shared the recording last Thursday night on Twitter.

"What is wrong with Nancy Pelosi?" Mr Giuliani said in a tweet that has since been deleted.

"Her speech pattern is bizarre."

Mr Trump himself tweeted a separate video of Ms Pelosi last Thursday night, an edited clip from Fox Business that spliced together moments from a 20-minute news conference and emphasised points where she had stumbled on her words.

"PELOSI STAMMERS THROUGH NEWS CONFERENCE," the President tweeted.

By Friday, the social media giants, already under pressure to fight online disinformation, were forced to respond.

Addressing the distorted video that made Ms Pelosi's speech sound slurred, YouTube said the video violated its standards and had been removed.

Facebook said that a third-party fact-checker had rated the video "false", but posts remained on the site and the company said it was trying to limit how widely the video was shared.

That video continued to be shared and viewed on Twitter, but the company declined to comment.

The videos surfaced online amid a particularly intense and public feud between Mr Trump and Ms Pelosi.

Each questioned the other's temperament and mental fitness in an exchange of personal insults last Thursday.

Ms Pelosi is working to stave off impeachment proceedings against Mr Trump that she believes could harm her party, while Mr Trump continues to defy Democratic efforts to subpoena documents and summon witnesses in the wake of the release of special counsel Robert Mueller's report last month.

But the videos also raised broader concerns about the roles of digital manipulation and disinformation in politics, particularly in the lead-up to the 2020 election.

NYTIMES

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