BONN, JUNE 13 -- About 100,000 people rallied for nuclear disarmament here today in the biggest demonstration in the West German capital since protests four years ago against deployment of U.S. medium-range missiles.

Speakers, including leaders of the opposition Social Democratic Party, warned the Bonn government against seeking to impose conditions that might stand in the way of a proposed U.S.-Soviet accord to slash arsenals of medium- and shorter-range missiles.

The demonstration was organized by the Social Democrats, the Greens party, labor unions and church groups under the slogan, "Take the First Step: Scrap Nuclear Missiles!"

The left-of-center Social Democrats, the largest opposition party, sought to use the rally to burnish its image with peace activists.

"The trickle of common sense must become a broader stream of peace," Hans-Jochen Vogel, who is to be elected party chairman of the Social Democrats on Sunday, told the crowd in a downtown park.

Vogel criticized Chancellor Helmut Kohl's center-right government for seeking to exclude 72 short-range missiles and their U.S.-controlled nuclear warheads from a planned superpower accord to bar such missiles from Europe.

Soviet officials have said that the West Germans can keep the Pershing IA missiles, but that the warheads must be removed as part of the deal.

Greens leader Petra Kelly, who drew the loudest applause of any of the speakers, accused Kohl's government of seeking to impose "megalomaniacal conditions" for an arms agreement.

Defense Minister Manfred Woerner issued a statement accusing the protesters of demonstrating against "the wrong government." He said that Kohl's coalition, by insisting on deployment of the U.S. medium-range missiles four years ago, had forced the Soviet Union to negotiate and thus paved the way for the expected arms deal.