BONN, NOV. 2 -- West Germany's government today rejected appeals by the United States, other western allies and its own top private economists to cut taxes earlier than planned to spur the nation's lackluster economic growth and thus help boost the world economy.

The joint statement by the economics and finance ministries came a day after Economics Minister Martin Bangemann ruled out trying to pump up the West German economy through a major shift to a looser monetary policy and lower interest rates.

The West German statements appeared to remove any remaining possibility that Bonn would adopt significantly more expansionary economic policies in the wake of last month's worldwide stock market plunge.

{However, that rebuff was cushioned by a more conciliatory statement yesterday from Karl Otto Poehl, president of the West German central bank, according to Washington Post Staff Writer Hobart Rowen. Poehl indicated in a speech in New York that the West German government is ready to accept some decline in the dollar against the German mark under present world economic conditions.

{Given huge trade imbalances "and strong divergences" in other economic policy areas, Poehl said it may be "less ambitious but more realistic" for the major monetary powers to seek some flexibility in exchange rates, rather than making an effort to "peg" rates at preconceived stable levels or within target zones.

{Poehl defended the West German government against the charge that it has been pursuing a high interest rate policy in violation of the spirit of the Louvre Accord, the economic policy agreement reached in February by the major economic powers. That agreement, in addition to aiming at exchange rate stability, called on Japan and West Germany to stimulate economic growth, while the United States reduced its budget deficit.

{"I would like to underline one point," Poehl said. "We are not at all interested in interest rates rising either in Germany or in the U.S.A." He said that the recent global push toward higher interest rates had originated in the United States "for well-known reasons."

{The German official said that "in the end, stable exchange rates are not a goal in themselves. What we are really aiming at is a coordinated process of noninflationary growth."}

A flare-up in the longstanding dispute between Washington and Bonn over West German economic policy helped to trigger Wall Street's historic collapse in prices on Oct. 19.

Since then, U.S. officials have expressed hope that Bonn would play a central role in bolstering the world economy by pushing up its domestic growth rate.

But two West German government sources, explaining the rationale behind today's statement, said that Bonn believes that it already has done as much as it can to raise its growth rate, and that new measures would risk kindling a dangerous rise in inflation.

The sources, who asked to remain unidentified, indicated that the government will consider new steps to promote growth only if the world economy appears set to slide into recession.

"We have done everything to get the maximum growth in 1988," one of the sources said. "If you do very much to boost the economy, then you have the problem of inflation."

Bonn officials said that they remain committed to international economic cooperation to help solve the problems that contributed to the stock market crash. They noted that the West German central bank has slightly relaxed its monetary policy in the past two weeks and nudged down short-term interest rates by a small amount.

But the government has made clear that it believes that the United States bears most of the blame for the world's economic troubles. Officials have criticized Washington for doing too little to reduce the federal budget deficit and the U.S. trade deficit.

Bangemann, complaining in a radio interview that the United States has sent conflicting signals about its dollar policy, said that the Americans "have not exactly qualified themselves as advisers."

The United States, joined by Britain and France, has contended that West Germany is not bearing its fair share of the responsibility for keeping the world economy moving.

In this view, a higher West German growth rate would cause its factories and consumers to buy more goods from abroad, and thus help to reduce the U.S. trade deficit.

The United States has urged specifically that West Germany reduce taxes sooner and by a larger amount than now planned. Bonn plans to trim taxes by $8 billion dollars at the start of next year, and by $23 billion dollars in 1990.

Today, West Germany's top five economics research institutes also urged the government to cut taxes sooner.

"Whatever serves to improve the climate for growth should be done as soon as possible," the institutes said in a joint report.

The government, responding directly to the institutes and indirectly to Washington and the other allies, said that a speedup of tax cuts would be harmful because it would widen Bonn's own budget deficit.

"Realization of the proposal, made repeatedly in the report, to bring forward the tax reform planned for 1990 would endanger the positive growth effects of the budget consolidation," the statement by the economics and finance ministries said.

It conceded that "it cannot be completely ruled out that the unrest on the stock markets and currency markets will bring with it new burdens for the economic development in West Germany." But it said that "continued upward movement in the economy at the current pace is more likely than a weakening."

The institutes predicted that the West German economy would grow by 1.75 percent this year and by 2 percent in 1988. That is less than the government's own forecasts for growth of about 2 percent this year and 2.5 percent next year.

The West German economy, despite inflation of less than 1 percent both last year and this year, has been growing significantly more slowly than other leading western economies.