Albert Gore Jr. Wednesday accused fellow Democratic candidate Michael Dukakis of making "unwise and irresponsible" comments about a U.S. nuclear strike against the Soviet Union. On the Republican side, Vice President George Bush was winding up an easy-does-it campaign swing in New York.

All three of the remaining major Democratic presidential candidates were campaigning in New York Wednesday, six days before the state's big primary with 255 national convention delegates at stake.Massachusetts Gov. Dukakis, in an interview published in Wednesday's New York Daily News, said he could envision using nuclear weapons if the Soviets invaded Europe and conventional weapons failed to stop them.

"I don't think it's going to happen," he said. But "we've got to be prepared to use nuclear force. Obviously with great restraint, only when there seems to be no other alternative."

Gore, at a breakfast with corporate executives on Long Island, characterized Dukakis' comments as saying "he would launch a nuclear first strike against the Soviet Union if they invaded Europe with conventional forces."

He said presidents and candidates for the office traditionally have avoided "the trap of spelling out in advance when the United States of America would use the awesome power contained in our nuclear arsenal."

Later, to reporters, Gore said, "Governor Dukakis made a significant mistake . . . that's unwise and irresponsible."

Gore also criticized rival Jesse Jackson for what he said was Jackson's comment several years ago that "he would unilaterally halt deployment" of missiles in Europe.

The three Democrats met Tuesday in the first of four debates preceding next Tuesday's New York primary. Bush, meanwhile, threw out the ball at the start of a New York Mets baseball game and talked of campaigning against "the ghost of Jimmy Carter."

The debate featured several sharp exchanges between Dukakis, the Democratic front-runner, and Gore, the Tennessee senator who needs a strong New York showing to revive his candidacy.

At one point, Gore declared that Dukakis had sounded a note of "enthusiasm" about an independent Palestinian state. Gore also criticized Jackson on the same issue, saying he disagreed "with the way Jesse Jackson advocates a Palestinian state."

Dukakis retorted that Gore was just plain wrong. "I didn't express enthusiasm for a Palestinian state yesterday," he said.