BONN, JULY 24 -- East Germany's four-month-old elected government teetered on the verge of collapse tonight, as the country's political parties battled to survive German unification.

The Liberal Party, which holds 23 seats in East Germany's 400-member legislature, known as the Volkskammer, pulled out of Prime Minister Lothar de Maiziere's five-party coalition government to protest his insistence on holding separate East and West German elections Dec. 2, which would favor smaller parties such as the deposed former Communists.

For the moment, de Maiziere retains his parliamentary majority, but his largest coalition partner, the left-of-center Social Democrats, said they may quit the government as soon as Wednesday.

Although all major parties are committed to unification, the process could be delayed if de Maiziere fails to retain a majority to pass important legislation.

The cause of the political strife is a dispute over whether East Germany should become part of West Germany on Dec. 1 or Dec. 2.

The exact date of accession could mean life or death to many small East German political parties because the two Germanys have markedly different election laws.

If East Germany decides to unify with the West on Dec. 1, the day before a scheduled all-German vote, West German law would allow only parties that win at least 5 percent of the vote to be represented in the new legislature. The Liberals and Social Democrats favor this measure and want all Germans to vote by the same rules.

If East Germany waits until Dec. 2 to hold elections with West Germany, then East German voters will choose representatives under their existing law -- with no 5 percent hurdle.

This scenario, supported by West German Chancellor Helmut Kohl and de Maiziere's Christian Democratic Union, could allow three small parties -- the right-wing German Social Union, the former Communists and Buendnis 90, the alliance of grassroots groups that organized last fall's anti-Communist marches -- to survive after unification.

West German officials have become enraged over the East German row. De Maiziere has been summoned by Kohl to his summer home in Austria for emergency talks Thursday.

But the Social Democrats, the largest opposition party in West Germany, argue that de Maiziere and Kohl are working together to assure the chancellor's reelection in December.

According to this theory, the ruling Christian Democrats want to help small East German leftist parties such as the former Communists and the grassroots groups stay alive so that they can drain votes from the largest left-of-center party, the Social Democrats.

Newspapers in both Germanys today accused de Maiziere of supporting a policy that would save the former Communists, who now call themselves the Party of Democratic Socialism, from extinction.

But de Maiziere, whose party supported the Communists before the peaceful revolution last fall, insisted that "my only personal goal" is to win concessions from Bonn on East Germans' rights to their property, secure employment, abortion and recognition of diplomas.

Some West Germans have said the quarrel in East Berlin proves that the East Germans are incapable of governing themselves. "The bitter controversy," the daily Stuttgarter Zeitung said, "reveals not a cold game of poker among political professionals but helplessness, incompetence and general exhaustion."