Investing.com -- A merger between Elon Musk's space exploration company SpaceX and his EV giant Tesla Inc. is inevitable and only a question of timing, according to early SpaceX investor Peter Diamandis.

Diamandis said Wednesday in a Bloomberg Television interview that the combination makes sense because it would give Elon Musk the super voting rights he has at SpaceX., but lacks at publicly held Tesla. Musk had 85.1% control at SpaceX before the company filed for an initial public offering.

"I put it not as a matter of if but only a matter of when those companies come together," said Diamandis, a founder of the XPrize Foundation and a podcast host who has spoken with Musk this year.

Merging the companies would give Musk "the ability to operate across all of this infrastructure," including a fleet of Cybercab robotaxis and Tesla vehicles with compute and power capability, creating "a global infrastructure on the ground and in space," Diamandis said.

Musk held talks about such a transaction prior to SpaceX's combination with xAI, Bloomberg reported in January. Diamandis also spoke to Musk about it broadly in both January and March.

A CNBC report published Tuesday also detailed how talks of a tie-up were reportedly routinely and openly discussed internally by emploees at both firms.

Diamandis first invested in SpaceX in the late 2000s and has started or backed several companies.