LONDON, JUNE 19 -- Britain has announced its deepest defense cuts in more than a decade and canceled a $1.1 billion order for new jet fighters in the government's first attempt to harvest a "peace dividend" and come to terms with the end of the Cold War.

While Prime Minister Margaret Thatcher has continued in speeches to sound the most hawkish notes of any Western leader, Defense Ministry officials have been quietly working to find ways to retool Britain's strategic doctrine and reduce spending at a time when the government is under pressure to increase expenditures on health, education and local tax relief.

During a two-day review of military spending in the House of Commons that ended this evening, Defense Secretary Tom King announced a cut of just over $1 billion in the country's $35 billion defense budget, as well as the cancellation of 33 new British-built Tornado strike aircraft that were to be purchased over the next few years.

King also confirmed that plans are being drawn up for major reductions in front-line army and air force units deployed in West Germany under the auspices of NATO. The Warsaw Pact, he told the Commons, has "to all intents and purposes ceased to exist."

Like Thatcher, King has been extremely cautious in discussing defense cuts, warning that the Soviet Union and Eastern Europe remain unstable and that NATO therefore cannot afford to let down its guard. He has made clear that Britain intends to maintain its own nuclear defense capability.

Nonetheless, his ministry's secret review, titled "Options for Change," has apparently caused deep anxiety among Britain's top military brass, some of whom feel shut out from the process. In recent days there have been reports in the British press in which unnamed senior military sources have expressed alarm about the size of reductions.

Last month, King announced a two-month spending freeze. Monday he said the ministry had temporarily suspended payments to private contractors while it instituted new controls on spending.

While the results of the ministry's review have not been disclosed, analysts are predicting further cuts of perhaps 10 to 15 percent over the next three to five years.

"There will be cuts but nothing as deep as what you may see in the United States," said military historian John Keegan, defense editor of the Daily Telegraph.

The cancellation of the Tornado aircraft is a bitter blow for the Royal Air Force, which this summer is celebrating the 50th anniversary of the Battle of Britain at a time when some critics are calling for it to be disbanded. The Royal Navy, which escaped large cuts drafted in the last defense review in 1981 only because of the Falklands war, is also reportedly slated for major reductions.

While the armed forces chiefs are resisting, the pressure for cuts is coming not only from traditional doves in the opposition Labor Party, but also from many formerly hawkish Conservatives. A member of King's own defense team, Alan Clark, minister of state for defense procurement, has declared that the Cold War is over. Clark, who received encouragement from Thatcher, has suggested British forces have no more business in continental Europe and proposed reducing the army and air force by half and the navy by a third.