The 35-nation Madrid conference to review the progress of detente reconvened today after its Christmas recess with a strong U.S. attack on continued Soviet violations of human rights and mutual accusations between the two blocs that confrontational politics would endanger the meeting.

In an opening statement to the conference plenary, U.S. delegation chief Max Kampelman charged that the word "detente" had ceased to have any significance and "does not exist as an accurate reference of East-West relations."

Soviet delegation leader Leonidas Iiyichov accused the United States later of waging a "psychological war" by raising human rights issues.

In his opening speech Iiyichov told the plenary that the success of the conference depended on a mandate for a European weapons reducing conference later this year. A Soviet-backed disarmament proposal has already been termed unacceptable by Western diplomats.

The Madrid meeting groups the United States, Canada and all the European nations except Albania in extended talks that are the continuation of the Conference on Security and Cooperation in Europe (CSCE) meeting held in Helsinki, Finland, in 1975. A first followup conference to review the Helsinki detente accords in Belgrade two years ago agreed on little more than to meet again in Madrid.Western diplomats at today's meeting indicated that in the present state of international tensions the most that could be hoped for was an agreement to hold a third followup meeting. m

Underlining the wide gulfs separating the two blocs, U.S. delegation leader Kampelman detailed harassment, arrests and trials of Soviet human rights activists that had been monitored while the Madrid meeting was in recess.

The Soviet delegation concentrated instead on disarmament proposals that would regroup the 35 CSCE nations again in a specific weapons reduction conference later this year.

Describing an arms reduction conference as the "central, pivotal and vital question" facing the Madrid meeting, Soviet delegation leader Ilyichov ruled out any preconditions to such a conference and urged that it should convene with no specific object other than discuss the need for weapons reductions.

By ruling out preconditions the Soviet delegate appeared to reject outright a French disarmament proposal that calls for a prior meeting that would agree on so-called confidence building measures before undertaking weapons reductions.