Soviet authorities began a major propaganda drive on the Polish crisis today with mass meetings throughout the country apparently organized to whip up public sentiment against Poland's independent trade union federation Solidarity.

Moscow television said tonight such meetings were held at "major factories and enterprises in the country," and a commentator explained that "it is difficult to hold back one's indignation when reading about the Gdansk congress" of Solidarity.

It was the first time since the outbreak of the Polish labor unrest a year ago that the Kremlin used the technique of staging meetings having the appearance of being spontaneous to rally public opinion behind a hardening Soviet position toward Poland.

Diplomatic observers here said the move was obviously intended to escalate further the pressure on Poland's communist authorities to crack down on the independent union.

But these observers also suggested that there was a distinct possibility that the Soviet government was trying to prepare its citizenry for an eventual intervention should the Polish government fail to combat what is described here as Solidarity's "direct call for a counterrevolution."

Today's mass meetings, as reported by Moscow television's main evening news broadcast, echoed a condemnation by the Tass news agency yesterday of the Gdansk congress. It was described as an "antisocialist and anti-Soviet orgy" that called for "open struggle" against the socialist system not only in Poland but also in all other Soviet Bloc countries.

The first session of the Solidarity congress, which ended Thursday, expressed support for independent trade union activists throughout the Soviet Bloc, called for free elections and challenged the Polish government to hold referendums on the critical issue of worker self-management.

Tass reported earlier today that about 70,000 workers at Moscow's Zil truck factory approved an open letter to the Polish workers in which they asserted that Solidarity was pushing Poland on "the road to capitalism and want to impose the yoke of exploitation on the worker."

Moscow television showed scenes from the Zil meeting and also from a similar gathering at the Kirov machine tool plant in Leningrad.

This was preceded by a report from the current Soviet military maneuvers around Poland's borders. It showed Soviet tanks engaged in mock battles and included scenes from Soviet naval maneuvers in the Bay of Gdansk with marines engaged in landing operations using hovercraft and supported by heavy armor disgorged from amphibious vessels, helicopters and jet aircraft.

The landing, which was conducted under poor weather conditions, took place near the Soviet city of Baltysk, about 30 miles from the Polish border, according to Western military experts. It was observed by Soviet Defense Minister Dmitri Ustinov, who is in overall command of the war games.

The letter of the Zil workers charged that Solidarity's "sole aim" was to undermine the basis of socialism in Poland.

"Therefore we are concerned about Poland's fate and this concern has further increased as a result of the congress of Solidarity," it said.

"The decisions of the Gdansk congress contain no hint of a desire to build socialism in Poland.

"We are especially angered by the so-called appeal to the workers of Eastern Europe adopted at the congress. We have read it, and we see that it contains nothing but malice against socialism.

"Such provocations have always aroused anger and protest in Soviet people. No other sentiments can be expected by those who raise their hand against a country and a heroic people to whom Poland and the leaders of Solidarity themselves--if they are not strangers on Polish soil--owe their existence."

The letter said it was "surprising" that Polish workers let their "enemies" use such words as "trade unions, working people and the interests of the people as a cover-up."

"Just ask yourselves -- have you become better off, is there more food on your table and is your home warmer now as a result of the alleged concern shown by Solidarity during the past year?" the letter asked.

It expressed the hope that the Polish working class "will muster enough strength, courage and determination to defend the gains of socialism and to stop the class enemy. In this, they may always rely on the solidarity and support of the Soviet people."

The reference to the deteriorating economic situation in Poland was apparently designed to buttress charges that Solidarity's aim was not to devote itself to trade union issues but rather to try to grab political power in Poland.