(Reuters) - JPMorgan Chase & Co (JPM) is likely to lead the underwriting of Chrysler Group LLC's initial public offering, CNBC reported late on Wednesday, citing a person familiar with the offer.

An IPO would bring to a head the battle between Sergio Marchionne, who leads both Chrysler and its main shareholder Fiat SpA (MIL:F), and a healthcare trust fund affiliated with the United Auto Workers union.

Chrysler plans to file documents this month that would allow its minority investor to sell shares in a stock market listing, a process that will slow Fiat's plans to take full control of the U.S. automaker.

The trust, a type known as a voluntary employees' beneficiary association or VEBA, is unhappy with the price Fiat has offered for its Chrysler stake and is exercising its right to push Marchionne to take Chrysler public.

A Chrysler spokeswoman declined comment to CNBC on the company's IPO. (http://link.reuters.com/xyc33v)

Chrysler and JPMorgan could not immediately be reached for comment by Reuters outside of regular U.S. business hours.

(Reporting by Sakthi Prasad in Bangalore; Editing by Edwina Gibbs)