Elon  Musk tweeted Friday that his Twitter deal is on hold as he waits for more details on the social media platform's estimate that spam and fake accounts make up less than 5% of its users.

Twitter’s (NYSE-TWTR) stock plunged nearly 20% following the tweet in pre-market trading. It closed at $45.08 Thursday on the New York Stock Exchange.

Musk's tweet read: Twitter deal temporarily on hold pending details supporting calculation that spam/fake accounts do indeed represent less than 5% of users.

The Tesla CEO, who is also the world's richest man, announced last month that he intends to buy Twitter for $44 billion. Musk had said one of his priorities would be to remove spam bots from the platform.

Twitter said in a filing Monday that spam accounts represented fewer than 5% of its monetizable daily active users during the first quarter. The company is yet to comment on Musk's latest tweet.

Billionaire Elon Musk is on record saying he would life the Twitter ban on former US president Donald Trump after buying the global messaging platform. Billionaire Elon Musk is on record saying he would life the Twitter ban on former US president Donald Trump after buying the global messaging platform. Photo: AFP / Brendan Smialowski