Donald Trump's campaign manager said Twitter made "a very dumb decision" after the president's favourite social media platform banned paid political advertising.

"Twitter just walked away from hundreds of millions of dollars of potential revenue," Brad Parscale said in a statement, adding that the new policy was another attempt to silence conservatives, and that Trump "has the most sophisticated online program ever known."

Jack Dorsey, the company's chief executive officer, announced on Wednesday that the platform would ban all political ads starting on November 22.

The move comes after Democratic candidates criticised Facebook for its policy of not fact-checking posts and paid ads from politicians, allowing them to use the platform to spread false information.