Elon Musk's $44 billion deal to buy Twitter is still in danger due to concerns over the number of bots on the social media site, according to reports.
Mr Musk has yet to receive clarity on the bots figure, despite being given access to internal data, The Washington Post reported.
His team is preparing for a “change in direction”, the Post said.
The world's richest person has previously threatened to withdraw from the deal unless proof that less than 5 per cent of accounts were spam and fake was provided.
At an event in Qatar last month, Mr Musk said he was still waiting for a resolution on the issue and “that is a very significant matter”.
Meanwhile, Twitter said in a briefing on Thursday that it removes a million spam accounts each day, and repeated that spam accounts were well under 5 per cent of users who are served advertising.
“Twitter has and will continue to co-operatively share information with Mr Musk to consummate the transaction in accordance with the terms of the merger agreement,” a company representative told Bloomberg News after the Washington Post published its story.
“We believe this agreement is in the best interest of all shareholders. We intend to close the transaction and enforce the merger agreement at the agreed price and terms.”
In May, a study by Israeli cyber-security company Cheq found that up to 12 per cent of visits to Twitter were from bots.
It analysed 5.21 million website visits originating from Twitter, using more than 2,000 cyber-security tests to determine each user's authenticity.
Research company Bot Sentinel estimated that 10 per cent to 15 per cent of accounts on Twitter are inauthentic, according to a Bloomberg report, while Cyabra, a research company with a different methodology, puts the percentage of inauthentic Twitter profiles at 13.7 per cent.
“The Twitter soap opera is clearly coming to some sort of finale over the coming months as Musk makes the decision to stay [with a lower price] or go,” Wedbush analyst Dan Ives said in a note to investors.
“The Twitter deal has clearly caused chaos at Twitter.”
Twitter’s board recommended in June that shareholders approve Mr Musk's deal.
A US Securities and Exchange Commission filing said the company's board “unanimously determined that the merger agreement is advisable, and the merger and the other transactions contemplated by the merger agreement are fair to, advisable and in the best interests of Twitter and its stockholders”.
Twitter's share price has slumped since Mr Musk's initial $54.20 a share offer as part of his proposed acquisition. The share price closed at $38.79 on Thursday. The stock has fallen 28.43 per cent since Mr Musk made the offer in April.