Western European allies today shied away from President Reagan's proposal to ban Soviet civil flights from their countries even as they voiced support for his harsh indictment of the Soviet role in the Korean airliner tragedy.

Most European governments individually have echoed Washington's condemnation of Moscow for failing to provide a credible explanation for the destruction of the South Korean jumbo jet last week in which 269 persons died.

But European nations so far have demurred from emulating Canada's decision to slap a two-month ban on Aeroflot flights because they do not wish to violate bilateral air travel treaties or provoke Soviet reprisals.

No such reluctance was indicated in London today by commercial pilots when the governing body of the International Federation of Airline Pilots' Associations, which has 57,000 members in 67 nations, recommended a two-month ban on flights to Moscow in retaliation for what they described as the deplorable Soviet destruction of a "defenseless civil airliner."

The British Air Line Pilots Association took up the recommendation and said it expected to implement it by Friday, halting four flights a week by British Airways to Moscow.

Despite the tensions generated by the airline incident, U.S. and Soviet negotiators met today in Geneva for the sixth and most crucial round of the nearly two-year-old negotiations on limiting medium-range missiles in Europe.

Chief U.S. delegate Paul H. Nitze and Yuli Kvitsinsky, leader of the Soviet delegation, met for almost two hours behind closed doors. Neither side would comment on today's talks.

West German government spokesman Peter Boenisch today described Reagan's speech last night in which he outlined limited sanctions against Moscow as "moderate and responsible." He said the West German government wanted to develop a unified allied response in Madrid this week when foreign ministers gather for the final session of the Conference on Security and Cooperation in Europe.

But Foreign Ministry officials said the Bonn government would strive to avoid an embargo on landing rights for Aeroflot, the Soviet national airline, because it feared possible Soviet countermeasures that could disrupt air traffic to West Berlin, located about 110 miles inside East Germany.

Other European countries, they said, are reluctant to take such steps as banning Aeroflot flights because their air travel treaties with Moscow generally require one year's notice of suspension.

Greece's reluctance to depart from the foreign policy stance of Prime Minister Andreas Papandreou prevented issuance of a statement condemning the Soviet Union's responsibility for the plane disaster by the 10-nation European Community this week, according to diplomatic sources in Athens cited by special correspondent Andriana Ierodiaconou.

A strongly condemnatory statement against Moscow was called for by the nine other member states, led by Britain and West Germany, the sources said. A draft proposal from Greece, which currently holds the presidency of the community, made no specific mention of the Soviet Union and was held by the other members to be too soft. Absent the required consensus on joint community policy, no statement was issued, the sources said.

France today said it wished to study Reagan's proposals and apparently wished to see what might emerge from a caucus of allied foreign ministers Wednesday in Madrid.

The French government also hoped to avoid worsening the East-West political climate before Soviet Foreign Minister Andrei Gromyko's stopover in Paris Friday.

British Foreign Secretary Geoffrey Howe said on his arrival in Madrid that it was important "for humanity to find a way of responding which will prevent such a thing from ever happening again."

But he dodged speculation over whether London would halt Aeroflot trips and said any action should be taken collectively, "not just on the basis of one nation's decision."

In Vienna, Chancellor Fred Sinowatz condemned the downing of the Korean plane but said neutral Austria would refrain from sanctions against Moscow.

In Tokyo, the Japanese government reacted cautiously to Reagan's speech and in its initial comments indicated it would not quickly act to restrict Aeroflot flights. Prime Minister Yasuhiro Nakasone told reporters today that Japan probably would wait for a further Soviet response before considering any sort of retaliatory action, correspondent William Chapman reported. Citizen groups in Japan and South Korea continued to protest the downing, however, and another group of relatives of the crash victims took a ferry ride into the sea near where the plane disappeared.

Canada is the only country so far to fulfill Reagan's request for reprisals in the aviation field. Shortly before Reagan's speech, Canadian Foreign Minister Allan MacEachen announced that Canada was suspending Aeroflot flights to Montreal for the next two months.

Behind the various pronouncements by national leaders, there was a distinct consensus that while Soviet behavior in the airplane tragedy should be censured in the strongest terms, the western allies should exercise prudence so that a vicious circle of reprisals does not cause a dangerous deterioration in East-West relations.

At the same time, the Europeans seem to recognize the need to express the force of their outrage so the western alliance does not appear complacent or feckless in the face of what is viewed as a gross breach of international conduct by the Soviets.

They also apparently believe that if they do not go far enough to satisfy U.S. indignation, the crisis could ultimately create tensions within the alliance.

West German officials, however, praised the close consultions in recent days and U.S. understanding of the problems the crisis raised in allied capitals.

The Netherlands, holding in abeyance any move on flights, showed its displeasure with Moscow today by canceling two official visits between the two governments.