Tesla Chief Executive Officer Elon Musk will join Twitter’s board of directors, the microblogging platform’s chief Parag Agarwal announced on Tuesday.

The development comes a day after Musk bought a 9.2% stake in Twitter, making him the biggest shareholder in the company.

“Through conversations with Elon in recent weeks, it became clear to us that he would bring great value to our Board,” Agarwal said. “He’s both a passionate believer and intense critic of the service which is exactly what we need on Twitter, and in the boardroom, to make us stronger in the long-term.”

Musk said that he was looking forward to working with Agarwal and the Twitter board of directors “to make significant improvements to Twitter in coming months”.

Twitter founder Jack Dorsey said he was “really happy” about Musk joining the company’s board of directors. “He cares deeply about our world and Twitter’s role in it,” he said. “Parag and Elon both lead with their hearts, and they will be an incredible team.”

Musk now owns 7.35 crore shares in Twitter, taking his passive stake in the company to $2.9 billion, (or about Rs 21,846 crore), according to filings with the United States Securities and Exchange Commission.

A passive stake is one in which the shareholder does not play an active role in running a company.

He now holds a stake in Twitter that is over four times larger than that of Dorsey.

Musk is very active on Twitter and has more than 80 million followers on the platform.

On March 25, he had launched a poll asking people if they believe Twitter rigorously adheres to the principle of free speech, to which 70.4% respondents answered in the negative. On the next day, he hinted at launching his own social media platform.

On April 5, he started on poll on Twitter asking them if they wanted an edit button. Agarwal urged the users to vote carefully.