Leaders of the Solidarity union movement last night approved plans for a warning strike in four northern provinces next week, the first major industrial protest in Poland since the government called a 60-day freeze on strikes in April.

Solidarity's National Commission, meeting without leader Lech Walesa, who was in Geneva, voted 22 to 13 with two abstentions to stage a two-hour warning strike in the cities of Bydgoszcz, Wloclawek, Plock and Torun next Thursday.

The job action was called to protest delay by the authorities in punishing officials responsible for ordering police to evict Solidarity members from the Bydgoszcz provincial assembly hall March 19.

Deputy Premier Mieczyslaw Rakowski met Solidarity leaders in Bydgoszcz. A Solidarity spokesman said Rakowski promised to meet again Monday to discuss their grievances. He said an agreement between the government and the unionists would cancel the strike call.

Some prominent members of Solidarity and of the powerful Roman Catholic Church expressed disapproval of the strike vote.

In a separate development, Moscow Radio said yesterday that "anti-Sovietism" is increasing among Poles and that loyal party members face increasing risk of violence from agitators, Washington Post correspondent Kevin Klose reported.

The official party newspaper Pravda, in a separate Tass report from Warsaw, quoted Stanislaw Wronski, chairman of the Soviet-Polish friendship society, as saying that "only those who are politically blind" can faill to see "a dirty flood of anti-Sovietism" in Poland.