Underground leaders of Poland's banned Solidarity trade union announced today that they will attempt to stage a program of mounting protests, leading to a general strike next spring.

In a statement made available to Western correspondents here, Solidarity's underground Coordinating Commission called for extending a nationwide four-hour strike planned for next month to eight hours and following it with demonstrations. It also called for a week of demonstrations beginning Dec. 13 -- the first anniversary of the imposition of martial law.

The statement said the commission decided to escalate the protests because the military government had proved "deaf to the nation's voice." It said that compromise and national agreement had become impossible as a result of what it termed "the illegal decision" to disband all existing trade unions and the repression of protest strikes and demonstrations last week.

The strike called for Nov. 10, two years after Solidarity was formally registered by the Polish supreme court, will be a key test of the underground's support in the country and its organizational ability. Last week, government spokesman Jerzy Urban said Solidarity no longer had the ability to mount effective coordinated protests.

If significant protests take place next month and the government continues to be unbending in its opposition to Solidarity, Poland could face several months of labor unrest and social tension. Authorities have warned that demonstrations could delay plans to lift martial law this year.

Meanwhile, the wife of interned Solidarity leader Lech Walesa accused the government of trying to pressure her husband into emigrating or joining a Communist-dominated movement for national salvation. Danuta Walesa had just returned to Gdansk from a visit to the government rest home in southeastern Poland where Walesa is being held.

She said he was in favor of continuing protests by workers following the outlawing of Solidarity by the Sejm, the national legislature, on Oct. 8. She quoted him as saying: "It is difficult to endorse the methods now being used, so every form of protest is good."

Mrs. Walesa said that after meeting with her husband for the first time in nearly a month, she was strip-searched -- apparently to prevent her from smuggling anything out -- and her children were also searched.

She told journalists that the conditions in which Walesa was being held had deteriorated and that he had not had any hot water for two months. Army officers had visited him recently and advised him to leave the country, she said, while Minister for Trade Unions Stanislaw Ciosek offered him freedom if he agreed to join a "patriotic movement for national salvation" that has been set up to support the authorities.

Mrs. Walesa said her husband refused both offers.

The decision to call for a general strike in early 1983 was described by Solidarity's underground commission as "a last resort" following the failure of 10 months of protests to soften the government's line.

Accusing the government of ignoring all pleas for reconciliation, including those put forward by the Roman Catholic Church, Solidarity's underground commission said: "The regime wants to rule uncontrolled by anybody. By arbitrary, incompetent decisions, it is ruining the economy and pushing Poland toward disaster."

The statement was signed by the five members of the Consultative Commission: Zbigniew Bujak from Warsaw, Piotr Bednarz from Wroclaw, Bogdan Lis from Gdansk, Wladyslaw Hardek from Krakow and Eugeniusz Szumiejko representing the union's national presidium.

It also called for "suitable commemorations" to mark Nov. 11, the anniversary of Poland regaining its independence after World War I.

The statement added: "Actions of civil resistance initiated by the union's leadership will reveal the utter isolation of the authorities and their collaborators, the ineffectiveness of repression, and the rule of terror."