BRITAIN has launched a diplomatic drive aimed at ending its long isolation in the European Community on economic and monetary union, and there are signs that the policy is bearing fruit. John Major, who was elected prime minister Nov. 27 following the resignation of Margaret Thatcher, spearheaded the new approach two days later. In a speech likely to mark a watershed in British policy toward the EC, he said Britain in the future would be ``whole-heartedly engaged'' in shaping Europe.
The tone of his remarks contrasted sharply with Thatcher's long-standing opposition to plans for a single European currency and central bank.
Mr. Major also let it be known that he had ordered the foreign secretary, Douglas Hurd, to produce a detailed document spelling out the new policy ahead of the EC's intergovernmental meetings in Rome on Dec. 14-15. These meetings have been called to take important decisions on European integration in the years ahead.
Major and Mr. Hurd are said to be confident that the policy formula will bring to an end the recrimination that soured relations between Britain and its EC partners in the latter years of the Thatcher premiership.
Pierre Beregovoy, the French foreign minister, welcomed Major's election. Last Friday one of his officials indicated France was prepared to take a step toward the British position with the aim of striking a compromise.
Government officials said Norman Lamont, Britain's newly appointed chancellor of the exchequer, was delighted by France's ``accommodating'' remarks. Mr. Lamont was attending an EC meeting in Rome Sunday to discuss economic and monetary union.
Last week, Hurd said that up until the time of Mrs. Thatcher's resignation he had failed to persuade her to publish an agreed Cabinet statement for European policy. But when Major held his first Cabinet meeting last Thursday, a prime minister official said the idea had gone through ``almost on the nod.''
But Major has not gone as far as some of his most pro-European ministers would like, including Hurd. This is because he came to the premiership with the support of about 50 members of parliament who share Thatcher's hard-line views on Europe.
He must move cautiously lest they interpret him as favoring a fully federal Europe and stage a revolt. This weekend Nicholas Ridley, a former Thatcher supporter, warned of the ``dangers'' of ``drifting into federalism.''
On Friday, a spokesman for the Bruges Group of Conservatives, named for an anti-federalist speech delivered by Thatcher two years ago, said: ``Mr. Major, we are watching you like a hawk.''
The key that promises to unlock the European door for Britain is Major's plan, devised six months ago, for a so-called ``hard ecu'' - a Euro-currency to run parallel to EC national currencies. Thatcher's guarded approach to European unity convinced the French and other EC governments that the hard ecu was simply a diversionary tactic.
Now that he is prime minister, Major has signaled that under his leadership Britain would regard the parallel currency as part of a process that may lead eventually to a single currency.
Within hours of Major making his position clear, French officials told their British counterparts that France, a strong advocate of a single currency, was prepared to look at the hard ecu plan sympathetically.
In his attempt to end Britain's isolation, while guarding his back against attacks by anti-federalist members of Parliament, Major is stressing that he will never let a single European currency be imposed on Britain against its will, officials say.
The compromise emerging promises to permit Britain to endorse moves toward a single currency and European central bank while choosing its own time to participate in the scheme.
This two-speed concept, British officials say, is likely to win acceptance by France. Karl-Otto Pohl, the governor of Germany's central bank, last Friday threw his support behind the two-speed concept.
The Major line also has won support from within the European Commission, the EC's executive arm. Henning Christopherson, vice president for economic affairs, says: ``Britain will never be forced to accept a common European currency.''
The prime minister's pledge that Britain in the future would play a constructive role in talks on economic and monetary union was ``a good sign,'' Mr. Christopherson says.