Poland's communist leadership took a major new step Friday toward dismantling the country's socialist system as the parliament approved laws removing controls on privately owned businesses and encouraging foreign investment.

Economists and party activists said passage of the laws, which were the subject of a 14-month battle within the party and government apparatus, represented the first significant measures in a "second stage" of economic reform in Poland. The program was first announced by party leader Gen. Wojciech Jaruzelski some 21/2 years ago but had been stalled ever since by bureaucratic resistance and high-level indecision.The new laws, which were revived and strengthened after the appointment of a new government in October under Prime Minister Mieczyslaw Rakowski, offer the private sector and foreign investors nearly equal conditions in the Polish economy with state-owned companies. They will, in theory, allow private entrepreneurs to start up firms without obtaining prior permits from authorities and guarantee them equal access to bank credits and supplies of raw materials.

The new law on economic activity also breaks ground within the Soviet Bloc by removing all limits on the size of a private business, meaning that Polish capitalists will be able to own factories with thousands of employees. Previously, private firms were limited to a maximum of 150 workers.> "We are no longer afraid of radical reforms," government spokesman Jerzy Urban said in explaining the measures. "The Poland you will see several years from now will have a different economy than it has had until now."

Independent and opposition economists generally praise the new reform laws but caution that it remains to be seen whether and how they will be implemented in practice. In recent years, even far less generous provisions for private enterprise were blocked on a day-to-day basis by the party and government bureaucracy, especially at the local level.

Activists of the banned Solidarity labor union also argue that the government's measures bypass the bulk of the economy that remains state-owned and state-managed. "Rakowski is working on the margins of the economy," said Jan Litynski, a Solidarity activist in Warsaw. "The system itself remains untouched."> Government officials say the two major laws passed Friday are part of a package of several dozen laws that will fundamentally restructure the economy over the next several years. Two bills already presented to parliament would create a commercial banking system next year and would legalize the black market in foreign exchange, in effect making the Polish zloty convertible with the dollar inside Poland.

Authorities clearly hope that the new laws will lead to quick increases in supplies of consumer goods and remove excess zlotys from the domestic market, eventually easing the shortages that have plagued Poland for a decade.>