The New York Times has "discontinued" a twice-weekly column about New York City by Sydney H. Schanberg, whose coverage of the communist takeover of Cambodia won the newspaper a Pulitzer Prize in 1976 and became the subject of a popular movie, "The Killing Fields."

Leonard Harris, director of corporate relations for The Times, said cancellation of the column after four years was announced yesterday by Sydney Gruson, vice chairman of The New York Times Co. Harris said that no reason was given and that another Times assignment for Schanberg is "under discussion."

Schanberg, who is 51 and has worked at The Times for more than 26 years, was told by Gruson of the decision yesterday after returning from two weeks' vacation.

"I guess all I really want to say is that I'm very proud of the column. I think it was an important column, and I think The Times should be proud of it," he said, adding later: "I realize it sounds self-serving."

Schanberg's supporters at the newspaper and outside said they think that the column, called "New York," was killed because in it, on July 27, he criticized what he believed was inadequate coverage by the city's newspapers of the proposed $4 billion Westway highway project through Manhattan.

Proposed in 1974, the project would consist of a 4.2-mile, six-lane underground highway on the lower West Side, a 93-acre park and 100 acres for residential and commercial real estate development. A federal judge earlier this month banned construction of the controversial highway. The state said it would appeal the ruling.

In his column, Schanberg called Westway, which The Times has supported on its editorial pages, a "scandal" and a "mega-boondoggle."

Saying New York's newspapers, including by implication The Times, had concentrated on "trivia" instead of investigating Westway, Schanberg concluded: "The New York dailies, strangely asleep, run only occasional bland stories, sometimes just snippets -- rarely anything about the chicanery. That, too, is part of the shame of Westway."

Some of those familiar with the Schanberg case said he is not the first Times columnist who has written critically about Westway.

They also suggested that the July 27 column, not Schanberg's first criticizing Westway but perhaps his toughest on The Times, was more symbolic than pivotal in the decision to discontinue the column.

"I think you'll hear speculation relating this to everything but the return of Halley's comet," Harris said. "Needless to say, that is frivolous speculation."

Harris added that "the paper also hopes to renew, at some point in time, a metropolitan affairs column."