Mr Penn wrote on May 10 that a new Matrix film was "possible" and he was excited for it.
"But it's Hollywood so don't believe it til the cameras roll," he wrote on Twitter.
He also firmly added that claims of a 'reboot' were misreported.
Discussing Film claims the new Matrix movie will start production in early 2020 in Chicago.
The news comes as Matrix star Keanu Reeves enjoys his career resurgence with fans dubbing him "the most wholesome person alive".
More than 70,000 fans have joined a bid for the actor to be named this year's Time Magazine's Person of the Year.
2019 has been massive for Reeves with performances in John Wick 3: Parabellum, Always Be My Maybe and Toy Story 4.
It was recently reported Reeves opted to give millions in his earnings from The Matrix sequels to the special effects team, because he felt they deserved it more.
He also reportedly gave a Matrix set worker $20,000 to help with family troubles.
It's claimed its been dubbed "project ice cream" and the original film's art director, Hugh Bateup, is on board. Bateup has been contact for comment.