NEW YORK, SEPT. 17 -- David Puttnam, one of the few independent producers ever to run a major Hollywood studio, is resigning as chairman of Columbia Pictures after only a year on the job, the company announced today.

Puttnam, a Briton whose credits include such acclaimed films as "Chariots of Fire" and "The Killing Fields" -- both made before he arrived at Columbia -- had two years left on his contract with the studio, which is owned by Coca-Cola Co.

His resignation comes less than three weeks after Coca-Cola announced that its entertainment businesses, including Columbia, would be merged with Tri-Star Pictures Inc.

Speculation had been rife in the film industry that the merger would force Puttnam out, even though Columbia would still be run as a separate entity. Coca-Cola said his decision to resign followed a meeting with Victor Kaufman, chairman and chief executive officer of Tri-Star.

Only last week Puttnam told Variety magazine that he intended to honor his contract at Columbia and would not be affected by the merger, but industry analysts said it was only a matter of time before Puttnam and Kaufman clashed.

Puttnam's hiring last year was widely viewed as a major gamble by Coca-Cola to reverse Columbia's declining fortunes. The studio, acquired by Coca-Cola in 1981, had suffered a series of management upheavals and a string of expensive box office flops.

The 46-year-old producer had established a solid creative reputation as an independent filmmaker but had never held an executive position with a U.S. studio. Hollywood executives are usually insiders with a background in entertainment production, finance or law. Moreover, Puttnam had antagonized many in Hollywood with his vociferous criticism of its free-spending ways and his apparent disdain for mass-market commercial cinema. But he said in a newspaper interview shortly after he took over at Columbia that he hoped to shrug off "this image that I'm some artsy European who makes art films."

Analysts have doubted that the three-year period of his contract would be long enough for Puttnam to make an imprint on Columbia because it often takes that long for a film to be developed and released. He did implement cost-cutting and reorganization measures at the studio, but Columbia was hit hard by the box office failure of "Ishtar," released this year. The film, a project of Puttnam's predecessor Guy McElwaine, starred Dustin Hoffman and Warren Beatty and was rumored to have cost more than $40 million. Other recent Columbia releases, such as "La Bamba" and "The Karate Kid Part II," have been successful without giving the studio the "megahit" it needs.

The test of Puttnam's own production slate was only beginning, with three pictures due to be released by the end of this year. Kaufman said today he would consider a number of candidates to take Puttnam's place.