The UAW could be inching Chrysler closer to an IPO.

In what could be the first step towards an initial public offering, the UAW's Retiree Medical Benefits Trust - better known as VEBA - has asked Chrysler to register 16.6 percent of its stock with investors.

Chrysler confirmed on Wednesday that it had received a "registration demand" from VEBA. The move is viewed as a way for VEBA to gain a better understanding on the true value of the automaker, as the registered shares could be sold on the private market or used to begin the IPO process.

"There can be no assurance that a registration statement will be filed with the Securities and Exchange Commission, or that if filed, that any such offering will be made or as to the timing of any offering that is made," Chrysler said in a statement. "The securities that are part of any such offering may not be sold nor may offers to buy be accepted prior to the time that a registration statement under the Securities Act becomes effective."

The timing of the UAW's request could be linked to a dispute with Fiat, which currently owns a 61.8 percent stake in Chrysler. Fiat has expressed interest in purchasing an additional 3.3 percent stake of VEBA's 41.5 percent Chrysler ownership, but the two sides have not been able to agree on a price. Fiat thinks the 3.3 percent share is worth $198 million while the UAW values it at $342 million.

The UAW has yet to comment on the matter, but we expect to learn more about the union's motivation in the coming weeks.