NEW YORK - With a threatened transit strike six days away, New York Mayor Michael R. Bloomberg yesterday outlined a series of contingency plans - including a virtual ban on single-occupant commuter automobiles in Manhattan - should the city's 34,000 subway workers and bus drivers walk off the job.

"New York will not be brought to its knees by an illegal, irresponsible strike," the mayor said, announcing emergency guidelines under which all highways, bridges and tunnels into Manhattan would be restricted to cars with four or more people during the workweek and two or more riders during the weekend.

Bloomberg, who frequently takes the subway to work, said he would bicycle to City Hall if a strike shuts the nation's largest public transportation system. "People in this city are tough," he said at a City Hall news conference, flanked by commissioners and agency heads. "They'll figure out how to cope."

New York's transit workers voted overwhelmingly last weekend to authorize a strike beginning Sunday, when their contract expires.

Union negotiators and the state-run Metropolitan Transportation Authority remain far apart; the Transit Workers Union is seeking a 24 percent raise over three years, and state officials are offering a wage freeze next year, with future raises tied to increased productivity.

Although state law specifically forbids strikes by public employees, TWU chief Roger Toussaint has refused to rule out a work stoppage.