Washington — The Reagan administration has shifted momentarily from a confrontational thrust in foreign policy to one of conciliation. President Reagan has decided to make a friendly gesture to Poland. Some say that it is also a gesture toward the Soviet Union. The United States is about to lift two of the economic and financial sanctions which it took against Poland nearly two years ago.
State Department officials say that the US will agree to negotiate over a renewal of Polish fishing rights in American waters and to reopen talks on the rescheduling of Poland's massive $14 billion-plus debt to Western governments. The Reagan administration had withdrawn the fishing rights and banned the debt talks after the Polish authorities imposed martial law in December 1981.
The administration's new moves are being taken in response to the successful visit of Pope John Paul II to Poland last summer and to the release of some - but not all - Polish political prisoners. There was considerable pressure from key West European allies in favor of such moves.
The administration's decision would place the US back in line with its allies , who have been urging that the West stop giving Poland the cold shoulder and start making moves that might encourage the Polish regime to ease its hold over the Polish people.
Some expert observers see the decision as an attempt to show flexibility not only toward the Polish authorities, but also toward the Soviet Union at a time when US-Soviet relations are at a low point.
Even before the administration's decision was announced, it was denounced by Lane Kirkland, head of the AFL-CIO, who said that there should be no easing of sanctions until all political prisoners were freed, free labor unions restored, and dialogue begun between the Polish government and the Solidarity labor movement.
But administration officials may have felt it especially important to bring the US into harmony with its European allies on this issue at a time when there is much European unhappiness with the US invasion of Grenada. Mr. Kirkland argued, in obvious reference to the deployment of US troops to both Grenada and Lebanon, that this was a sign of weakness.
''If we falter in our resolve with regard to Poland, our demonstrations in force elsewhere in the world will not suffice to restore credibility . . . ,'' said Kirkland.
Agreeing with Kirkland's criticisms were Sen. Bob Kasten, the Wisconsin Republican who heads the foreign operations subcommittee of the Senate Appropriations Committee, and Richard T. Davies, a former US ambassador to Poland.
Senator Kasten argued that the liberalizing moves made so far by the Polish authorities have ''not really been significant'' and that they still hold ''large numbers of prisoners.''
Kasten, who has held hearings on the Polish debt question, said that he would try to organize opposition in the Congress to the administration's move and would explore ways of blocking it through the appropriations process.
Ambassador Davies contended that the decision was ''part of some kind of strategy to mollify the Soviet Union.''
''There will be enormous disillusionment and disappointment among the Polish people,'' Davies said. ''Up to now, Reagan had been something of a hero over there.''
But Jiri Valenta, currently on leave as coordinator of Soviet and East European Studies at the Naval Postgraduate School in Monterey, Calif., argues that the US has nothing to lose by moving in a limited way to lift sanctions against Poland.
Dr. Valenta, who is currently a fellow here at the Woodrow Wilson International Center for Scholars, is convinced that the West can influence the Polish regime only ''at the margins,'' but that it can increase its leverage over the regime by reopening talks on the debt question.
''My guess is that they will respond,'' he said. ''They might release more prisoners.''
Valenta adds, however, that it is doubtful that the regime would allow anything like a revival of the outlawed Solidarity labor union movement. He doubts that the Soviet Union would permit this.