Elon Musk has offered to buy Twitter for £31 billion.
The Tesla boss recently announced he had become the largest shareholder in the social media site, having bought a 9.2 percent stake in the company.
But according to reports, Musk has now offered $54.20 per share to take full control.
In a letter to Twitter chairman Bret Taylor, Musk said: "Since making my investment I now realise the company will neither thrive nor serve this societal imperative in its current form.
"Twitter needs to be transformed as a private company. My offer is my best and final offer and if it is not accepted, I would need to reconsider my position as a shareholder."
Today's development follows on from Musk's decision last week to not join Twitter's board.
Had he done so, as he originally planned, he would have been limited in the amount of control he would have been allowed to command in the company.
Board members are not permitted to have more than a 14.9 percent stake during their time on the board and 90 days after.
Twitter Chief Executive Parag Agrawal said: "Elon’s appointment to the board was to become officially effective 4/9, but Elon shared that same morning that he will no longer be joining the board.
"I believe this is for the best. We have and will always value input from our shareholders whether they are on our board or not. Elon is our biggest shareholder and we will remain open to his input."
Since taking a huge stake in the tech giant, Musk has already proposed a couple of major changes.
Just last week, he suggested transforming Twitter's headquarters in San Francisco into a homeless shelter.
The SpaceX boss took to Twitter to highlight some of the changes he'd like to see at the company and even asked his millions of followers if they agree with him.
These proposals included making the service cheaper, banning advertising, and even having the option to pay in cryptocurrency.
In typical fashion, Musk tweeted: “Maybe even an option to pay in Doge?”
He also seemingly took aim at the Twitter staff choosing to still work from home and said the office could be used in a more constructive manner.
He set up a poll that asked: “Convert Twitter SF HQ to homeless shelter since no one shows up anyway?”
The poll hit more than 1.9 million votes, with 91.3 per cent of voters in favour of the proposition.