Twitter Inc areset to agree a sale to entrepreneur, Elon Musk, worth around $43 billion in cash, the price the CEO of Tesla has called his "best and final" offer for the social media company, close sources have stated.

Twitter may announce that it will be accepting Elon Musk's $54.20-per-share deal later today. The companies board of directors have met with Twitter's shareholders to discuss the transaction, however, sources have said that the deal could collapse at the last minute.

Musk, who is the world's richest person according to Forbes, is negotiating to buy Twitter. Tesla, his other company, will not be involved in the deal.

Twitter has not been able to secure a 'go-shop' provision under its agreement with Musk, which would allow it to solicit other bids once the deal is signed. However, Twitter would be allowed to accept an offer from another party by paying Musk a break-up fee.

Mr Musk, a prolific Twitter user, has said that the company needs to be made private in an effort for it to grow and become a genuine platform for free speech.

The 50-year-old entrepreneur, who is also CEO of rocket developer SpaceX, has said he wants to combat trolls on Twitter and proposed changes to the Twitter Blue premium subscription service, including slashing its price and banning advertising.

Mr Musk, a billionaire, and a vocal advocate of cryptocurrencies, has also suggested adding the cryptocurrency, dogecoin, as a potential payment option on Twitter.

He has said Twitter's current leadership team are 'incapable of getting the company's stock to his offer price on its own', but stopped short of saying it needs to be replaced.

"The company will neither thrive nor serve this societal imperative in its current form," Elon Musk said in his offer letter, just last week.