Poland's military authorities tonight announced a sharp reduction in cultural and scientific ties with the United States in apparent retaliation for continued U.S. sanctions despite plans to ease martial law.

The Polish moves, which include the introduction of visa restrictions on Americans and the interruption of all cooperation with the U.S. Information Agency, were announced in an official communique. The statement said they were in response to "far-reaching American restrictions" that had even been stepped up in recent days.

[In Washington, the State Department had no immediate comment.]

The government's measures were foreshadowed by a speech on Dec. 3 in which the Polish leader, Gen. Wojciech Jaruzelski, accused the Reagan administration of being blinded by "an anti-Polish obsession." The immediate cause appears to be disappointment at the failure of Western governments to react positively to moves by the Polish parliament to suspend many martial-law restrictions.

U.S. officials have said that the suspension of major restrictions of martial law, which parliament is expected to approve on Saturday, does not go far enough to meet President Reagan's conditions for restoring normal relations. These include the lifting of martial law altogether, the release of "all political prisoners" and the resumption of dialogue between the Polish authorities and independent institutions such as the church and "representative trade unions."

U.S. sanctions against Poland include suspension of agricultural credits, restrictions on Polish diplomats, bans on Polish fishermen operating in U.S. waters, bans on high-technology exports to Poland and withdrawal of most-favored-nation tariff status.

The United States also has blocked Poland's bids to reschedule its foreign debt and join the International Monetary Fund.

The main target of the Polish counter-measures is the U.S. Information Agency, which runs a library in Warsaw and arranges cultural, educational and scientific exchanges.

The Polish move is binding on "all ministries, institutions and individuals." This presumably means that Polish citizens will no longer be allowed, for example, to visit the library.

The polish statement accused American espionage agencies of repeatedly abusing "scientific and cultural cooperation for the purposes of penetration and subversion." It also attacked two U.S.-financed radio stations broadcasting in Polish, Radio Free Europe and the Voide of America, which it said had stepped up "the aggressiveness of their programs."

The Polish government said that cooperation would be cut with "all U.S. federal agencies" that engaged in anti-Polish activity -- a clause that could allow the extension of restrictions to other areas. It said "a special procedure" would be introduced in considering "any invitations and grants or trainee offers" connected with cultural and scientific exchanges.

Outlining new visa restrictions, the statement said Poland would suspend "the granting of visas to any representatives or employes of the United States Information Agency or its branches." It added that "all visa applications from the United States" would be considered "with an eye to the interests and security of the state."

It was not immediately clear whether the visa restrictions would affect only U.S. officials or also employes of private companies.

During the past few weeks, Polish officials have expressed particular outrage at a remark by the U.S. Secretary of Defense Caspar W. Weinberger depicting Jaruzelski as a Soviet puppet.

Weinberger described the Polish leader as "a Russian general wearing a Polish uniform" -- a wounding insult to someone who considers himself a patriot acting in Poland's best interests.