The Soviet Union announced tonight it will send extra food and manufactured goods to Poland in a move to soften the economic impact of the strikes that have brought unprecedented new power to Polish workers.

The official Tass press agency offered no details, but the agreement signed today by top Soviet and Polish trad officials here underscored Warsaw's precarious economic position and Moscow's willingness to extend help and further strengthen its own position in the Polish economy. Warsaw has estimated strike losses so far at more than $1 billion.

Earlier today, Tass said, Soviet President Leonid Brezhnev met Mieczyslaw Jagielski, the Polish deputy premier who negotiated the settlement allowing independent trade unions and the right to strike.

Tass said the two discussed "questions of further consolidation and development of all-around relations" between the two countries."It was imphasized that in present-day conditions, it is particularly important to comprehensively enhance the efficiency of Soviet-Polish economic cooperation" bilaterally and within Come-con, the Moscow-dominated East Bloc economic group.

Yesterday, Jagielski met with Mikhail Suslov, the Stalin-era Politburo ideologist who is believed to have criticized the concessions. Tass said the two had "exchanged opinions on questions of mutual interest," and official phrasing that implies some discord.

Western sources here view the Polish mission as an attempt by the new government of Stanislaw Kania to reassure the Kremlin, which has both sharply denounced the strikers and congratulated Kania on suceeding the ousted Edward Gierek. Continued Soviet nervousness over Poland was visible today in the Communist Party paped Pravda's suggestion that the Polish communists have lost the confidence of Poles, Pravda said that at meetings of party activists in Warsaw, Gdansk and Katowice, "it is being said these days that the working class is being serously tested, that the most important task of the [party] now is to restore the confidence of the working class and all the working people in the party."