Negotiations once again collapsed today in the three-week-old labor dispute between the American Ballet Theatre and its dancers, and as of late in the day no further negotiations were scheduled.

ABT had predicted yesterday that the dancers would accept a new contract by Tuesday. But today the company warned the performers that the four-week Kennedy Center season, set for December, will be canceled on Oct. 12 if no contract agreement exists by then.

ABT also said that its January engagement in Miami is approaching possible cancellation. Previously ABT canceled its October Paris performances and said it will cancel its November Boston engagement on Tuesday if it is still at odds with the dancers.

Today, for the first time in the dispute, the dancers' comments were openly acrimonious. "All management is talking about is cancellation," said dancers' spokesman Frank Smith. "They had no new offer to make today. . . . We said, 'You want to cancel, so cancel.'

"We've heard that before," Smith added, referring to the bitter labor dispute of 1979 when ABT did cancel its Kennedy Center December season. "I have a feeling they won't take us seriously until they have canceled another [Washington] season, just like last time," he said.

ABT officials could not be reached for comment.

Although the two sides are still sharply in dispute over travel expenses, work-rule issues and fringe benefits, they are, according to the dancers, only about $100,000 apart on the issue of wages. The $100,000 represents the total difference over the next three years -- the length of a new contract sought by both sides.

To the dancers' demand for wage parity with the higher-paid dancers of the New York City Ballet, ABT has responded by offering an immediate one-year parity, requiring a 28-percent wage increase this season. But ABT offered second- and third-year increases of about 6 percent and 5 percent while the dancers are demanding increases of 7 and 9 percent. ABT dancers currently earn a minimum of $16,000 a year.

The dancers also say they won't return to work without payment of the wages they lost since ABT locked them out on Sept. 2, a demand ABT has refused.