Brussels — The Reagan administration's economic policies are prompting swift protests from West Europe.
Washington's allies want to avoid what is seen here as a possible new and major source of trans-Atlantic frictions.
But with unemployment breaking the psychologically important barrier of 10 million, European Community countries have dispatched special emissaries to Washington and are beginning to ponder a more active response as well.
They regard the US budget and interest rate policies as so destabilizing that they could drive a deeper wedge in the Western alliance.
A German official bluntly noted ''it's an open secret that our government feels that the American policies don't help European economic recovery and maybe not even the American economy.''
The trouble is that there has already been considerable friction between Washington and Western Europe over the allies' response to the military crackdown in Poland and the subsequent American demand for economic pressure on Moscow and Warsaw. Hence, EC leaders are extremely worried about further exacerbating the American public and official hostility toward them on essentially economic issues.
Belgian Prime Minister Wilfried Martens and Foreign Minister Leo Tindemans were dispatched to Washington this week to try to deal with these mounting problems. In his Brussels office just before his departure, Mr. Tindemans noted in an interview:
''I have American friends who write me and say 'take care. You underestimate what is going on for the moment in the United States;' and when I read editorial and opinions and so on, I think it's true.''
After meeting with President Reagan in the White House Feb. 17 Prime Minister Martens said, ''The Atlantic alliance and the Western dconomies are going through very difficult times and our solidarity is being put to a test.''
The American actions which have triggered such a strong reaction in Europe are the same which have touched off the domestic US debate. They have reached a certain peak since President Reagan's budget message and the subsequent rise in American interest rates in response to the expected budget deficit.
They have also had to cope with another round of international monetary instability as dealers have once again switched from their European currencies to the rising yields on the dollar. This has, in turn, provoked more disparities between the value of European currencies themselves on the one hand and between them and the dollar as well on the other hand. For EC countries, which depend much more than the US on international trade, such monetary upheavals can have serious repercussions.
EC finance ministers meeting here earlier this week also agreed that they would like to see a change in US official attitudes toward the budget deficit, toward the policy of non-intervention in the money markets to avoid upheavals like the current one, and about announcing monetary and inflation targets which cause further commotions on these currency markets when they are announced and frequently not reached.
But just as importantly, it has resulted in greater conviction that European governments should drop their own interest rates, despite the possible impact on their currencies and inflation, instead of continuing to follow the American trend.