Elon Musk stated last week that he had secured $46.5 billion in finance to buy the company, prompting speculation that a transaction is near. Twitter’s board of directors met on Sunday to consider Musk’s offer to buy all of the company’s shares that he doesn’t already hold for $54.20 each, according to a source familiar with the matter. According to the insider, conversations over Musk’s offer have become serious.

Musk appeared to hint at the completion of a deal on Twitter on Monday when he tweeted, “I hope that even my worst critics remain on Twitter, because that is what free speech means.”

The potential sale agreement caps off a whirlwind news cycle that began less than a month ago, when Musk revealed he had taken a more than 9% stake in the company and ramped up calls for changes to the social media platform.

Questions about whether Musk would actually be able to finance his acquisition of Twitter swirled in the days following his takeover bid, especially after he said in an interview the day of his offer that, “I’m not sure I’ll actually be able to acquire [Twitter].”

Shares of Twitter (TWTR) had been trading noticeably below the offer price in a possible signal of investor skepticism about the deal. On Monday morning, however, Twitter stock rose nearly 5% following the reports, topping $51 a share.

“I invested in Twitter as I believe in its potential to be the platform for free speech around the globe, and I believe free speech is a societal imperative for a functioning democracy,” Musk said his offer letter to Twitter. “However, since making my investment I now realize the company will neither thrive nor serve this societal imperative in its current form. Twitter needs to be transformed as a private company.”

However, according to CFRA senior equities analyst Angelo Zino, Twitter’s board of directors may be taking Musk’s offer more seriously because “an alternative bid from a ‘white knight’ may be tough to come by, especially given the recent decrease in asset prices from social media businesses.”