The ban affects only paid content, - ads placed and purchased by political campaigns or individuals for a price, but it does not otherwise limit what users may say on the platform.
Twitter's ban of paid political adverts may not have much impact on the campaign for the presidency, it does heighten pressure on rival Facebook over its policy of not fact-checking ads from politicians.
Civil rights activist Reverend Al Sharpton said on Thursday that he and other civil rights leaders would meet with Facebook CEO Mark Zuckerberg next week to discuss the policy.
"I have deep concerns that this policy is a misinformation vehicle that could aid voter suppression and voter misinformation efforts, and it should be stopped immediately," Sharpton said in a statement.
Facebook has also been under fire for its political ads policy from Democratic presidential candidates such as former Vice President Joe Biden and Senator Elizabeth Warren.
"This saves Twitter a big headache in a market that makes them almost no money. But it doesn't help anyone else - in fact it hurts candidates and the voting public," tweeted Jessica Alter, co-founder of Tech for Campaigns, a nonprofit that helps Democrats with digital strategies.
A senior adviser on the campaign of Democratic contender Mayor Pete Buttigieg also said Twitter's move could hurt lesser-known political candidates trying to spread their message.
"I think the ban helps power the incumbency. Instead of policing the forum, they took the easy way out and banned everyone, which will hurt challengers trying to get involved in the process," the adviser told Reuters.
A Trump campaign official reacted on Thursday that Twitter's decision to scrap political advertising will have little effect on the re-election campaign of Trump, the candidate who spent the most on digital ads in the 2020 election.
"I never love when a channel, a pipe, is turned off because it eliminates an opportunity," the senior official told reporters on a conference call the day after Twitter CEO Jack Dorsey announced the ban. "But it won’t significantly impact us."
The Trump campaign and its backers have spent just over US$6,000 promoting an official @TeamTrump Twitter account for the president's campaign. Twitter's records show no spending to promote tweets by Trump's @realDonaldTrump account, which he uses prolifically and which has over 66 million followers.
In comparison, the campaign has spent more than US$21.3 million on Facebook ads since May 2018, according to data published by Facebook.
The 18 Democratic candidates in the 2020 election and their backers have spent over US$5.4 million promoting tweets since May 2018, compared to at least US$52.2 million on ads run through their Facebook pages, according to a Reuters review of data from the companies' public ad libraries.
The overall political ad spend for the 2018 U.S. midterm elections on Twitter was less than US$3 million, Twitter's Chief Financial Officer Ned Segal said in a tweet on Wednesday.