Western European governments are urging the United States to set aside technical and political reservations and join in an emergency multibillion-dollar package of assistance to help Poland pull out of its economic and political crisis, officials in several European capitals said today.

American sources stressed that substantial problems still must be overcome by the 15 Western nations and more than 100 banks to which nearly bankrupt Poland is already deeply in debt. But the Europeans, led by Bonn and Paris, are reported to be insisting that a definite commitment to swift aid is necessary. They appear to have agreed in return to join the Reagan administration in emphasizing publicly that this assistance will be conditional of Poland's remaining free of violent repression from the Soviet Union or hard-liners within Poland.

Despite the U.S. hesitation, European officials said they expect U.S. support for speeded-up negotiations to meet Poland's request for a $10.9 billion rescue package.

American officials and bankers are reported by Western European sources to be particularly concerned that further financial assistance to Poland on such a massive scale be conditional on an acceptable plan for economic recovery. Such a plan would be similar to requirements for emergency reserve loans made by the International Monetary Fund, of which Poland is not a member.

The current deliberations follow a tentative settlement yesterday that averted a showdown between the Polish government and its independent unions and a U.S. warning that a "suppression" of the Polish labor movement would foreclose any further U.S. economic aid.

A critical date in these deliberations seems to be next Wednesday, when representatives of the 15 Western governments are scheduled to meet in Paris to discuss a package of longterm refinancing and new export credits for Poland.

A parallel session was scheduled for next Wednesday between representatives of the Polish State Bank and Western bank officials. Bankers from 12 countries representing 40 banks held a meeting with Polish State Bank officials here today and decided to continue talks tomorrow. A spokesman for the bankers said "a satisfactory solution can only be achieved through calm and restrained discussion taking place on continuing basis."

Polish Deputy Prime Minister Mieczyslaw Jagielski is scheduled to begin talks about the Polish aid request with the Reagan administration in Washington on Wednesday after receiving a public promise from French President Valery Giscard d'Estaing in Paris today of support for a package of long-term financial assistance in addition to immediate European Community food aid.

In Bonn today, West German Chancellor Helmut Schmidt also gave public assurances of his government's support for both immediate emergency help and long-term financial aid for Poland.

Schmidt also reiterated that continued Western aid to Poland was contingent on a peaceful solution to its crisis.

"If it comes to the use of force, then it is not only the credits which would stop, the world would change," Schmidt told reporters after a meeting with Irish Prime Minister Charles Haughey, who was making a 24-hour visit to Bonn. Both men emphasized Poland's need for emergency food and financial assistance. The situation was so serious, Haughey said, that "food aid is simply a necessity."

Tons of butter, meat, milk powder, grains, sugar, edible oil and animal feed are being supplied by the European Community to Poland at below world prices with credit provided by the 10 member nations.

European officials said a majority of Western nations had reacted "positively" to Poland's request for the $10.9 billion package of longer-term financial aid. It includes $3.4 billion in new export credits guaranteed by Western governments, rescheduling of payments falling due this year on $4.4 billion already owed by Poland to Western governments, and a similar rescheduling of $3.1 billion owed this year by Poland on unguaranteed loans from Western banks.

The representatives of the 15 Western nations to which Poland now owes an estimated $23 billion already decided at a meeting in Paris last month to recommend that their governments give Poland emergency assistance by deferring loan payments due during the first quarter of this year. West Germany, France and Britain are among the countries said ready to extend it for another three months.