Banishing President Donald Trump from Twitter (TWTR) could weigh on the social media giant’s share price and wipe billions of dollars of its market valuation, a Wall Street analyst has warned.

Twitter is facing growing calls from some disgruntled members of the public to put an end to Trump’s steady stream of polarizing tweets. However, according to James Cakmak, an analyst at Monness Crespi Hardt & Co, if Twitter gives into demands to block his @realDonaldTrump account, it will be committing corporate suicide.

In an interview with Bloomberg, Cakmak said that banishing Trump from Twitter’s website could cost the San Francisco-based company as much as $2 billion, nearly one-fifth of its $11.91 billion market capitalization. Cakmak is confident that Trump’s absence from Twitter won't lead his 36.2 million followers, and numerous other members, to quit the blogging website. However, he does believe that the loss of one of its most prominent users will rattle investor confidence.

According to Cakmak, blocking Trump could have a striking impact on Twitter’s intangible value and potentially lead to multiple compression, an effect that causes a company's price-to-earnings multiple to fall due to wariness surrounding its growth prospects.

“There is no better free advertising in the world than the president of the United States,” Cakmak said in the interview. (See also: Twitter CEO Says Trump's Tweets Are 'Important'.)

Cakmak, who has a neutral rating on Twitter’s stock, also made a number of other observations about the company. In a note published on Thursday, the Wall Street analyst claimed that Twitter’s business must do a better job of capitalizing on the opportunities it has in order to succeed.

“What’s most important is the execution of the right strategy, since at the present state we find Twitter not capitalizing on the opportunity that’s in front of them,” he said in the note.

Twitter told investors in July that its number of daily active users had risen 12 percent in the second quarter. According to Cakmak’s estimates, Twitter now has roughly 125 million daily users, 30 percent less than Snap Inc (SNAP).

Cakmak’s statement about Trump’s importance to Twitter came after a Marist poll, reported on by USA Today, said 72 percent of those surveyed viewed his tweets as “reckless and distracting." Critics believe Trump’s tweets are harmful to the country and national security and have urged Twitter, which is taking steps to crack down on hate speech and harassment, to ban him from its platform. (See also: Twitter's Trump Bump May Be Coming to an End.)

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