BERLIN, OCT. 4 -- The first all-German parliament in 57 years began the work of a new country today with a meeting in Berlin's Reichstag, the imperial building that still bears the scars of Nazi Germany's rise and fall.

Helmut Kohl, in his first speech as chancellor of the reunited nation, promised that "the coming years will show that the united Germany is a gain for all Europe." The new Germany, he said, will be a bridge between East and West and will devote itself to the creation of a United States of Europe.

With 144 new members from the now-dissolved East German parliament, the expanded Bundestag observed a moment of silence in honor of the 100 German legislators who died at the hands of the Nazis or the Stalinist regime that ruled East Germany.

"A free and united parliament in a free and united Berlin in a free and united Germany," proclaimed Bundestag president Rita Suessmuth. "What a day in the parliamentary history of our country!"

While one of the two surviving members of the pre-Nazi Weimar Republic legislature looked on from the balcony, the 663 lawmakers greeted five new ministers, including former East German prime minister Lothar de Maiziere, former parliamentary president Sabine Bergmann-Pohl and three other veterans of East Germany's only freely elected government. The five will join Kohl's interim government as ministers without portfolio.

The 16 million former East Germans who became citizens of the united nation on Wednesday will get their first say in the composition of their government when all-German elections are held Dec. 2.

Today's meeting quickly turned into a practice round for the all-German election campaign that begins in earnest next week. Kohl's speech was laden with partisan shots at his challenger, Social Democrat Oskar Lafontaine.

Although the speed and smoothness of unification have given Kohl his highest approval rating in opinion polls, the chancellor has remained on the offensive, lambasting Lafontaine today for his persistent criticism of the costs of merging the two countries.

Having absorbed a million East Germans and other East European refugees in the past year while still reducing unemployment, Germany has the economic strength to rebuild the economy and rescue the environment of the old East Germany, Kohl said.

"When, if not now, were we better prepared?" the chancellor asked. He appealed to Germans to be patient with the costs of unity, warning that it could cost more than $650 billion to repair the damage that the Communist regime inflicted over 40 years of neglect and corruption.

Lafontaine responded by warning against a new German nationalism. "Germany is not just a 'fatherland'," he said, arguing that that patriotic term has been overused in the celebrations of recent days. "It is a motherland, too."

Lafontaine said he would push for more liberal abortion laws -- abortions are legal on former East German territory and largely illegal in the West -- and shorter working hours. Germans already have the second shortest workweek in the world.

The challenger, who is trailing so badly in polls that party leaders are talking publicly about asking Kohl if he would accept them in a coalition government, tried to set himself apart from the chancellor's strong endorsement of the North Atlantic Treaty Organization by calling for the removal of all nuclear weapons from German soil.

Protesting low-level training flights over Germany by U.S. and other Western air forces, Lafontaine asked, "Against whom are these maneuvers directed?"

Kohl said the new Germany will take on "greater responsibility" in the world and predicted that Bonn will soon be asked to add to the $2 billion it has pledged toward the international military buildup in the Persian Gulf.

The chancellor announced that Soviet President Mikhail Gorbachev will visit Germany in November to sign a friendship treaty, and Kohl called on NATO and the Warsaw Pact to agree to a friendship pact at the summit of 34 European and North American nations in Paris in November.

The opening parliamentary session in Germany's new capital was largely symbolic. Beginning Friday, the parliament will hold its working sessions in Bonn, the former West German capital, which remains the seat of government until early next year when the newly elected parliament is expected to rule on the expensive but popular proposal to move all official functions 400 miles east to Berlin.

The enlarged Bundestag is taxing the capacity of the small town that served as West Germany's capital for four decades. Some new legislators will live in hotel rooms; the chairman of the former East German communist party, Gregor Gysi, has been given an office in a converted kindergarten.