Soviets Ask for $20 Billion to Prop Up Ruble : Economy: Moscow calls for Western governments to commit about double the amount it sought as recently as July.

The Soviet Union, reflecting the continuing rapid deterioration of its economy, has asked Western governments to commit as much as $20 billion to assuring the stability of the ruble--about double the amount it sought as recently as July.

The figure was presented over the weekend here in unprecedented meetings between the Soviet Union’s chief economic policy-makers and those of the world’s largest industrial countries, known as the Group of Seven. A copy of the Soviet proposal was obtained Monday by The Times.

The United States and other Western governments have opposed establishing such a currency-strengthening fund, however, until the Soviets are further along in transforming their economy from state-run communism into a market-driven system. Until that happens, they say, any amount of money would be a waste--and no amount would be enough.

The Group of Seven--which includes finance ministers and central bankers from the United States, Germany, Japan, Britain, Italy, France and Canada--was meeting in a prelude to the annual meetings of the International Monetary Fund and World Bank that begin today.

The Soviet Union will be attending those sessions for the first time as a “special associate” member, with access to the technical expertise--but not the funds--of the two international lending institutions.

In his report to the Group of Seven, economist Grigory Yavlinsky, a reformer who heads the Soviet Committee for Management of the National Economy, described the “profound economic crisis” that faces his country and unveiled the latest blueprint for drastic reform of the Soviet economic system.

That effort could be eased considerably if the 12 republics of the Soviet Union commit themselves to an economic union treaty. Soviet officials on Monday postponed signing of a treaty until at least Friday, saying more time was needed to conclude some accompanying agreements.

The Soviet Union cannot be fully integrated into the world economy unless the ruble can be converted into other currencies. But without a fund of hard currency to back up the ruble’s value, the Soviets fear that their currency would immediately plummet to virtual worthlessness--making the country’s economic situation even more dire.

Only three months ago, the Soviets had told Western leaders that they wanted a stabilization fund of $10 billion to $12 billion.

In recent weeks, however, it has become apparent that the Soviets have even fewer assets available to back up their own currency than previously thought. The government has virtually wiped out its hard currency holdings and now says it sold two-thirds of its horde of gold in the past year.

The first stage of Yavlinsky’s blueprint for economic reconstruction would include the signing of the treaty, assuring that the 12 republics operate with a single currency, tariff system and trade zone.

During the second phase, the Soviets would seek to stabilize their economy by coordinating the budgets of the various authorities. Every republic now sets its own budget, an awkward mechanism that has ignited inflation to the point where prices are roughly double what they were last year.

Yavlinsky vowed that the government would cut overall spending by decreasing the military budget, reducing the bureaucracy, eliminating many of the subsidies that have been an integral part of Soviet life and freezing social programs.

The republics’ banks would be merged into a single central bank that would control monetary policy. Wage and price controls would be lifted on all goods, possibly excluding certain types of fuel, transportation and raw materials.

In the third phase, the ruble would become convertible. The Soviets would also open up trade with the rest of the world, although that would be done only gradually, because they realize that they produce little that people in other countries want to buy.