MOSCOW, JUNE 8 -- A campaign for still more far-reaching proposals to overhaul the Soviet economy is heating up here, as Mikhail Gorbachev and others in the Kremlin leadership near key decisions on the future of economic reform.

A meeting of the Communist Party's Central Committee on economic issues, due this week, has been postponed until later in the month amid signs of an intensifying struggle between reformers and conservatives.

The issue, aired in blunt articles and interviews in the press, centers on the choice between the "plan" and the "market," a dilemma which cuts to the heart of the current political and ideological debate.

Some reformers have gone so far as to argue that no reform is possible without a clean break with the Soviet Union's heavily centralized planned economic system. The Communist Party newspaper Pravda on Sunday printed a brusque response, defending central planning as an "indisputable achievement" of socialism and accusing those who argue differently of offering "indigestible" alternatives.

"It is a question of polarization," said one western diplomat. "The reformers are disturbed that the first steps have had no effect whatsoever, and they are therefore pushing harder, and therefore arousing greater reaction."

With increasing intensity, reform economists have warned that more "half-hearted" measures will doom reforms to failure, as happened in the past. One noted that the first steps taken under Gorbachev's two-year-old program have been only a "palliative," and that fundamental issues have still not been addressed.

The recent articles have called into question some of the most sacred of Soviet economic principles: the supremacy of centralized planning, state-held property, full employment and the idea that the Soviet system, based on Marxist-Leninist principles, is ideologically inviolable.

"The state of our economy satisfies no one," began an article by the economist Nikolai Shmelev, published in this month's Novy Mir, a literary journal that is now acquiring a reputation for publishing articles on the cutting edge of economic debate.

Shmelev, an economist at the Institute for U.S. and Canadian Studies, called the Soviet economy "virtually unplannable," and said the system had spawned a lethargy and skepticism among workers that could take generations to overcome.

Shmelev starts from the premise that the abandonment in the 1920s of Vladimir Lenin's New Economic Policy, which had allowed limited private enterprise and more local control, complicated the task of building socialism in the Soviet Union in "the most serious way."

Attacking the "administrative socialism" that developed under Joseph Stalin in place of the New Economic Policy, Shmelev challenges authorities to lose their "ideological virginity," accept minimum unemployment, overhaul the system of prices, taxes and credit, and turn the Soviet ruble into a convertible currency that can be exchanged on western markets.

An immediate improvement in goods and supplies is needed to restore people's shattered faith, Shmelev writes. "If people's hopes of a rebirth of common sense are not justified, then apathy could become irreversible," he said.

The article, now the talk of Moscow, would have been heresy here at any other time, diplomats noted. "It could be a liberal American economics professor taking a critical look at the Soviet economy," said one western diplomat.

Equally sharp views about the inadequacies of initial attempts at reform were aired this week in the weekly Literaturnaya Gazeta under the headline, "Economy at the Crossroads."

The state planning agencies -- in particular the central planning agency Gosplan -- and ministries came under attack for failing to give up their power, and for perverting reforms aimed at putting factories and enterprises on a "self-financing" footing.

"I am afraid that under the guise of self-financing, something opposite has crawled in," said Pavel Bunich, a corresponding member of the Soviet Academy of Sciences and frequent advocate of economic reform. He noted that central agencies in Moscow are still controlling distribution of a local factory's "profits," although this runs counter to the spirit of Gorbachev's reforms.

The recent spate of articles confirms the growing popular view that Gorbachev's economic reforms, launched with appealing slogans, are foundering on internal contradictions and uncertainties.

At the center of the current debate is the proposed law on state enterprises, which has been under public discussion since January and is due for adoption at the plenum this month. The draft law would give more power to local factory managers and provide workers with a greater voice. It has been criticized by reformers as self-contradictory and as typical of attempts to "neutralize" change.

In their own defense, representatives from the central agencies point out the system's goals are not as clear as they used to be.

"You know, it is very difficult to proceed -- we don't have a scientific conception," said V. Shcherbikov from the state Committee on Labor and Social Questions. "For years, theoreticians were proving to us that the most important thing distinguishing socialism from capitalism was the {system of social} guarantees. Now, we do not always know what is meant by 'end result.' Often, behind the ringing phrase, there is nothing."

Since Gorbachev announced last winter that a June plenum would be devoted to the "economic mechanism," experts have anticipated a revamping of the central planning apparatus, principally of Gosplan, the planning agency. According to some reports, Gosplan's staff -- which numbers 3,000, not including its adjunct research institutes -- could face a 50 percent cutback. Similar reductions are expected at the state Supply Committee and perhaps at the big ministries.

Earlier this year, as Gorbachev took a more cautious approach on economic questions, expectations for the plenum had toned down. But in recent weeks, articles in the press suggested a new push underway by those who would like to see further loosening of central controls, more encouragement of private incentives, and freer rein for "market" influences on the Soviet economy, without sacrificing socialist principles.

The conservative side of the argument is less often heard, but it is believed to have powerful representatives at the top of the Soviet power structure. Politburo member Yegor Ligachev, who ranks second after Gorbachev in the party hierarchy, is believed to be a leading critic of any "market-style" reforms. In a speech in the Georgian capital of Tbilisi this week, he warned that the "class enemy" could take advantage of reforms to undermine faith in the Soviet system.

Some diplomats speculated this week that the shake-up within the Soviet military, precipitated by Kremlin embarrassment over the surprise landing of a West German airplane on Red Square, could strengthen the hands of the reformers. The powerful Soviet military-industrial complex, the one area where Soviet products match world standards, has been viewed as one possible model for economic revitalization, with its emphasis on discipline, quality and large enterprises.