The Reagan administration yesterday reiterated its continuing interest in arms reduction negotiations with the Soviet Union, despite the decision not to launch new strategic arms talks next week as originally planned.

State Department spokesman Dean Fischer, reading a statement, said, "The administration's interest in meaningful arms reduction negotiations, including reductions in strategic arms, is undiminished."

Fischer would not confirm widespread reports, emanating from senior officials, that Secretary of State Alexander M. Haig Jr. will not launch the new arms negotiations in his meeting in Geneva Tuesday with Soviet Foreign Minister Andrei A. Gromyko. However, Fischer's comments broadly hinted at this by drawing a link between the Polish situation and arms control negotiations.

The Soviet Union is aware, according to Fischer, that the strategic arms negotiations "cannot be insulated from other events."

The spokesman went on to quote Haig as saying that "the continuing repression of the Polish people, in which Soviet responsibility is clear, obviously constitutes a major setback for prospects for constructive East-West relations." Fischer added, "There can be no question that the climate of East-West relations in turn has a serious effect on the prospects for moving forward in arms control."

It is far from clear, despite this assertion of "linkage," that the Polish situation will have a long-term effect on the strategic arms negotiations, which are known by the administration as START (strategic arms reduction talks).

The State Department made a point of saying that "our work on START is continuing." A senior official involved in policy making regarding the talks said that in his opinion the opening of negotiations with the Russians probably will not be delayed more than "a couple of weeks" from the previous schedule. The official and others suggested that a high-level Soviet-American meeting is not necessary for launching the negotiations.