Carl Icahn speaking at Delivering Alpha in New York on Sept. 13, 2016.

Activist investor Carl Icahn reported an increased 8.3 percent stake in Dell tracking stock on Monday, as he looks to block a proposed plan by the computer maker to return to the public market without an IPO.

Dell Technologies in July said it would pay $21.7 billion in cash and stock to buy back shares tied to its interest in software company VMware.

Icahn and other hedge fund investors have resisted the plan, saying the proposed deal massively undervalues the tracking stock.

"I intend to do everything in my power to STOP this proposed DVMT merger," Icahn said in an open letter to stockholders. "It is better to have peace than war, but be assured, I still enjoy a good fight for the right reasons."

Dell said earlier this month that it had met with some investment banks to explore an initial public offering if its plan to buy the tracking stock of VMware falls through.

Elliott Management and Canyon Capital Advisors have also resisted Dell's effort to buy back the "tracking stock" from them, arguing that Dell's offer inflates its own value and discounts the tracking stock's value.

A tracking stock tracks, or depends, on the financial performance of a specific business unit or operating division of a company, rather than the operations of the issuer as a whole.

"The Dell Tracker currently sells for approximately $92 per share but is worth on a pure mathematical basis approximately $144 per share," Carl Icahn said.

Dell and Silver Lake did not immediately respond to requests for comment.

Icahn previously owned 1.2 percent in Dell tracking stock, and the latest stake would make him the second largest shareholder in the Dell tracking stock.

Icahn said the best way forward would be to offer a competing partial bid that provides partial liquidity without forcing a merger, adding that he was looking at interested parties, including financing sources, who may want to finance such a bid.