Management at The Times and The Sunday Times, two of the world's most famous publications, tonight shut down their newspapers indefinitely.

The papers will stay closed, management has said, until all 65 unions agree to wide-ranging demands for a cut in staff, new labor-saving technology and an end to wildcat strikes.

In a Fleet Street saddened by the loss of such noted competitors, the estimate is that the two Times will be down at least six weeks. Times executives, backed with tens of millions of dollars, are figuring on two to three months.

A farewell editorial in the daily Times this morning was headed, "There Will Be an Interval." It said, "It is quite certain that The Times will return" and insisted the papers were doing Britain and Fleet Street "a service" by "seeking to deal with the growing anarchy."

The editorial bore the unmistakable stamp of editor William Rees-Mogg. In a signed article on Wednesday, he noted there have been fewer Times editors than popes in the last 160 years, but both "have an unqualified responsibility to protect the integrity and continuity of our institutions."

Joe Wade, general secretary of the National Graphical Association, whose union of linotypists' would be hardest hit by the new technology, has growled that "The Times management wants to go from Caxton to computer overnight." William Caxton, who lived in the 15th century, was the first English printer.

Wade insisted that bosses at the two papers "are not only hell-bent on introducing new technology on their terms, they are also hell-bent on bulldozing the unions and their members into abject surrender."

The Times, with a modest national circulation of 293,000 is no longer "the thunderer" of the 19th century, the paper that daily instructed Parliament. It is now a quaint, almost eccentric journal, beloved by elderly academics, clergymen, civil servants, politicians and retired generals.

As the suspension neared, one reader wrote to the daily's famous letters page that he would wear a rose in his buttonhole when The Times reappears. Another declared that "since life will cease to be civilized without The Times," he would grow a beard.

The Sunday Times, with 1.4 million circulation, has a different editor -- Harold Evans -- and a completely different staff. It is one of the world's greatest newspapers, doggedly pursuing serious inquires into the most sensitive and secret corners of the British establishment.

Both are owned by Lord Kenneth Thomson, whose father, Roy, bought and cherished the papers. The present lord lives in Toronto and rarely leaves Canada. He inherited an oil, press and travel empire that will give him an estimated $250 million in profits before taxes this year.

Tonight's shutdown climaxes months of non-negotiations that would baffle any American industrial relations specialist. The papers' management announced last April 26 that the journals would close Nov. 30 unless the unions accepted all the company's demands.

But no serious bargaining could begin until Oct. 15, six weeks before the deadline, when the employers for the first time spelled out some of what they had in mind. As late as Nov. 8, management still had not told the unions the full extent of their "sweeteners" -- proposals for pay, pension and holiday increases in return for cuts in the labor force.

Even now it is difficult to determine how many employes the two papers want to let go. The best estimates, from company sources, is about 750 of 4,300, almost all in the blue collar crafts. None would be fired outright. They would disappear through retirement, moving and other causes.

Marmaduke J. Hussey, the managing director or chief executive of Times Newspapers, has insisted there was ample time to make a deal, that a deadline was the only way to produce serious bargaining.

Wade's linotype union refused to bargain at all while the suspension threat hung over the talks. Today, neither his union nor the Times team met for a last-ditch effort at a settlement.

The other 64 unions have accepted a Times plan to halt wildcats. Seventeen locals, most of them small and covering less than 20 percent of the staff, have accepted the rest of the package. But that is all that appears to have been produced since the April 26 letter.

Wade's linotype union refused to bargain at all while the suspension threat hung over the talks. Today, neither his union or the Times met for a last-ditch effort at a settlement.

The other 53 unions have accepted a Times plan to halt wildcats. Four of the 53, mostly unaffected by staff cuts, have accepted the rest of the package. But that is all that appears to have been produced since the April 26 letter.

The Guardian, the closest rival to The Times, called the management bargaining technique "an error" that "dictates a scrabble against the clock."

In Toronto, Lord Thomson let it be known that he will come over to take a look next week. He called the affair "tragic" and a "nightmare" and said he had no intention of permanently closing or selling the papers.

His father, who delighted in board-room lunches with the famous at The Times, once said of the daily: "It is England. It is the flag."

Journalists at the two papers, who make $200 to $400 a week, are the least affected and best protected in the dispute. Those serving abroad are being kept on the payroll and those who face dismissal notices next week get up to four months of severance pay.

The craft unions, led by linotypists who make as much as $560 a week, get as little as two weeks severance pay. They plan to tax working members and share the work elsewhere in Fleet Street to hold out. How long they can against the Thomson resources is a serious question.