California Senator Kamala Harris asked Twitter to suspend US President Trump's account

California Senator Kamala Harris, who is a 2020 Democrat presidential candidate, has asked Twitter to suspend US President Donald Trump's account for attacking lawmakers and the whisteblower behind a complaint on his shady dealings with Ukraine.

"Trump's Twitter account should be suspended. There's plenty of evidence to suggest that he is irresponsible with his words in a way that could result in harm also the privilege of using those words in that way should probably be taken from him," Ms Harris told CNN on Monday.

"If you look at what he's been tweeting today directed at the whistleblower, I frankly think that based on this and all we've seen before, including attacking members of Congress, that his Twitter account should be suspended," she added.

Mr Trump pressured Ukrainian President Volodymyr Zelensky in a July 25 phone call to cooperate with his personal attorney Rudy Giuliani and Attorney General William Barr to investigate a Ukrainian gas company that might be related to former Vice President Joe Biden's son, Hunter, according to a transcript of the call released last week by the White House.

The US House Intelligence Committee has subpoenaed Giuliani, asking him to cooperate with the ongoing impeachment inquiry against Mr Trump launched by the House Democrats on September 24 and provide documents related to his dealings with Ukraine.

Mr Trump continued to defend himself against the accusations. "We're trying to find out about a whistleblower. We have a whistleblower that reports things that were incorrect," he said at the White House.

Twitter was yet to respond to Ms Harris' call. According to Twitter policy, "blocking a world leader from Twitter or removing their controversial tweets would hide important information people should be able to see and debate".

Mr Trump has repeatedly used Twitter to attack his political opponents.

In a series of tweets, he said that House Intelligence chairman Adam Schiff should be arrested for treason for exaggerating parts of phone call Mr Trump had with Mr Zelensky.

"Adam Schiff illegally made up a fake and terrible statement, pretended it to be mine as the most important part of my call to the Ukrainian President, and read it aloud to Congress and the American people. It bore no relationship to what I said on the call. Arrest for Treason?" he tweeted.