Chancellor Helmut Kohl told the first meeting of unified Germany's Parliament Thursday that Germans must never forget the Nazi Holocaust as they shape a new nation.

For the first time in nearly six decades, German lawmakers met in the Reichstag, prewar Germany's Parliament building.The ceremonial session one day after unification brought together 664 deputies - 520 from the West and 144 from the East - who will serve until elections on Dec. 2.

Parliament Speaker Rita Suessmuth opened the session, welcoming the lawmakers to the newly refurbished chamber decorated with flowers and with the huge eagle that symbolizes Germany.

"We remember all the victims of the Nazis and we remember the victims of the SED regime (East Germany's ousted Communists), the victims of the Berlin Wall and barbed wire," she said.

The lawmakers then stood for a moment of silence.

Kohl told them: "We must never forget, suppress or play down the crimes committed in this century by Germans. Above all we owe this to the victims of the Holocaust, the unparalleled genocide of European Jews."

The chancellor also condemned the Communists who until last autumn ruled eastern Germany. He said their dictatorship and repression had left behind "wounds in people's hearts."

Billions of dollars are needed to rebuild the devastated economy left by the Communists, and already the wealthy west is complaining about the cost.

"It is now essential to ensure that Germany is also swiftly reunited in economic and social terms," Kohl said. "This will call for great exertions, and we shall also have to make sacrifices."

The Reichstag, still scarred by World War II, had not hosted Parliament since it was gutted by a mysterious fire on Feb. 27, 1933, one month after Adolf Hitler became chancellor.

Leaders of the new Germany assured the world Wednesday, the official day of unification, that it would strive for peace and never forget the harsh lessons of its Nazi past.

Unification officially came after midnight Tuesday, and Germans across the new nation celebrated into Wednesday, their newest national holiday.

About 20,000 leftist radicals protesting unity rampaged in Berlin on Wednesday afternoon and evening. Police fired tear gas and water cannons in street battles, and about 50 people were arrested.

Numerous heads of state from around the world sent cables of congratulations to Kohl and the German people.

A goverment spokesman said Soviet President Mikhail Gorbachev, widely credited with making unification possible, will visit Germany next month. A hero's welcome is expected.

Kohl joined President Richard von Weizsaecker and other promiment politicians for a ceremony at Philarmonic Hall in Berlin, once again the nation's capital. Von Weizsaecker also urged Germans to remember and guard against their Nazi past.

"The Nazi terror and the war it caused inflicted untold serious injustice and suffering on almost all of Europe and on us," he said. "We continuously recall the victims."