PARIS, OCT. 19 -- Britain, France and West Germany endorsed the U.S. attack on Iranian oil platforms today but European officials took care to avoid associating their own warships with U.S. military policy in the Persian Gulf.

This European position reflected differing views on how best to meet the dangers created by Iran-Iraq hostilities and a lingering lack of confidence in the Reagan administration since the U.S. pullout from joint peace-keeping duties in Lebanon in 1983, a high-ranking European official said.

The government of Prime Minister Margaret Thatcher, who has strongly supported President Reagan in the past, said in London that the United States was "fully entitled to take military action in exercise of its rights of self-defense in the face of the imminent threat of further attacks."

Foreign Secretary Geoffrey Howe declared in the statement that Iran's attack Friday on a U.S.-flagged Kuwaiti vessel constituted "a flagrant abuse of the rules of international order" and added: "I trust the Iranians will fully understand that continuing attacks of this kind will only enhance the justification for firm action in self-defense."

France, the other major allied power with a dozen warships in the gulf area, underlined the right of every state "to act in the respect of international law and the United Nations Charter with a view to halting attacks such as the one of which a U.S.-flagged oil tanker was the victim Oct. 16."

The French statement underlined support for freedom of navigation in the gulf but expressed concern lest the U.S.-Iranian hostilities "bring a new escalation of the conflict, with the consequences that would result for neighboring countries."

Italy, the Netherlands and Belgium, the other three European countries whose warships have been sent to the area, refrained from immediate comment.

In Bonn, spokesman Friedhelm Ost said, "West Germany voices its understanding for the decision of the United States to exercise its right of self-defense under Article 51 of the U.N. Charter and to ensure the freedom of navigation by taking a limited action in the gulf.

"West Germany calls on the participants in the conflict to give a positive answer to the renewed efforts of the U.N. secretary general" to end the war, Ost said.

Bonn says that its constitution bars dispatch of warships outside NATO areas. An official, who asked not to be identified, noted that the attack was "calibrated" and the United States did well to pick a target in international waters rather than on Iranian soil.

Italian, Dutch and Belgian leaders, along with those of Britain and France, declined a U.S. request last spring that they send mine sweepers to join U.S. naval forces in the gulf as part of a NATO deployment. But by September, following separate French and British deployments, all major European allies except West Germany had dispatched warships to the region.

At the same time, they have sought since the beginning to dissociate their military vessels from U.S. ships' declared mission of protecting commercial navigation from Iranian attacks. A European defense official said one reason was fear of being drawn into a conflict with Iran because of U.S. decisions.

In an example of this concern, British naval officials emphasized to reporters in London that their ships were not near the pair of Iranian oil platforms shelled by U.S. ships this morning. Only the frigate Andromeda was in the gulf and it was just inside the Strait of Hormuz, they said.

British ships have been sailing into the gulf, accompanying British merchant craft. But under Royal Navy rules, officials recalled, they go only as far as Bahrain, approximately halfway from the Strait of Hormuz to the head of the gulf at the Shatt al Arab, and have carefully defined their mission as protection of British ships.

Similarly, a French official pointed out that French missile frigates accompany French merchant vessels into the gulf with the same limited mission and had nothing to do with today's U.S. shelling. He added that French naval forces usually remain in the Sea of Oman, outside the gulf proper, and French mine sweepers have been working off the emirate of Fujairah without entering the gulf.

European officials acknowledged that the presence of their warships in and around the Persian Gulf has created an indirect association with U.S. policy against Iran, despite their efforts to prevent it. President Hafez Assad of Syria, an ally of Iran, complained about this to Foreign Minister Jean-Bernard Raimond during his visit to Damascus earlier this month, a diplomatic source reported.

Washington Post correspondents Karen DeYoung in London and Robert J. McCartney in Bonn contributed to this report.