MOSCOW -- As the Soviet parliament hesitated on the brink of radical economic change, President Mikhail S. Gorbachev yesterday unexpectedly proposed holding a national referendum on whether to legalize private ownership of land.
Mr. Gorbachev also called "totally unacceptable" the tone of a rally of 30,000 Muscovites Sunday to demand the resignation of Prime Minister Nikolai I. Ryzhkov and his ministers, as well as more decisive market reforms.
But the leadership of the largest Soviet republic, the Russian Federation, said it will begin on Oct. 1 to implement the radical plan the republic has adopted whether or not the union parliament has made a decision. That plan, named for economist and Gorbachev adviser Stanislav S. Shatalin, includes the sale of land to private interests.
The developments suggested that the agreement of Mr. Gorbachev and Russian President Boris N. Yeltsin to push for a rapid, coordinated move to a market economy was in danger of coming unraveled.
While both men essentially back the Shatalin plan, a referendum would take weeks or months and could significantly delay or even derail implementation. Russian Prime Minister Ivan S. Silayev yesterday called the situation too critical to brook delay for a referendum and said he and Mr. Yeltsin would not await its results.
Addressing the U.S.S.R. Supreme Soviet, Mr. Gorbachev called the privatization of land "the most difficult issue" posed by the abandonment of central planning and the move to a competitive market.
"It is too big a decision, comrades, to be made in offices, auditoriums or meeting halls -- even the one in which we're working today," he said.
"The question of whether there should be private ownership of land or not is the sovereign right of the people to decide, and it can be decided only by a referendum."
V.I. Lenin's Decree on Land, issued the day after the Bolsheviks seized power in November 1917, declared Russian land "the property of the whole people." Beginning in 1929 Josef V. Stalin put an end to the last vestiges of private landholding by forcing the peasants on to collective farms in a murderous campaign.
The Gorbachev reforms already have authorized the long-term leasing of land by individuals, who also have the right to pass it on to their heirs. But few people have taken advantage of the lease law, partly because they fear reconfiscation of the land or because can't get good land from local officials.
Mr. Gorbachev's call for a vote -- which would be the first national referendum in Soviet history -- was a surprise. Mr. Gorbachev had not mentioned the idea in numerous recent speeches on economic reform and had himself rejected a similar suggestion early this summer.
Other roadblocks to rapid passage of the Shatalin plan appeared yesterday.
Soviet Deputy Prime Minister Leonid I. Abalkin, who defended the government's more cautious alternative to the Shatalin plan, said no major economic plan could legally begin without approval by a special session of the Congress of People's Deputies, as the Supreme Soviet's parent body is called. Calling a congress would significantly delay the beginning of any economic plan.
And despite initial signs that the parliament's majority would back the Shatalin plan's 500-day transition to a decentralized market economy, many deputies appeared frightened by the consequences of a too rapid denationalization of the economy and deregulation of prices.
Historian Roy A. Medvedev, a former dissident whose views now appear relatively conservative in this radicalized society, said he was rethinking his initial inclination to back the Shatalin plan.
He said that in the West market economies had not been formed over 500 days, but over 500 years.
An outsider added his voice to the debate yesterday. Former President Ronald Reagan, visiting with his wife, Nancy, at the invitation of Mr. Gorbachev, spoke to the Supreme Soviet's Committee on Foreign Affairs about the difference between planned and market economies and the benefits of entrepreneurship.
Mr. Reagan's remarks were generally well-received, but some present said he seemed unaware that market economics have been the subject of a constant public discussion here for the past year.
"He was preaching to the converted, and he didn't seem to realize it," one Western diplomat remarked.