The Soviet government added an extraordinary twist to its peace drive today by having two of its top military commanders appear at a news conference to express the conviction that arms limitations and reductions were "in the interests of both the United States and the Soviet Union."

The two generals asserted that U.S. attempts to gain strategic superiority would inevitably fail and pointedly noted that the Soviet people are prepared for "additional efforts" to ensure adequate security for their country.

All of this has been said before, but the appearance of General of the Army Valentin Varenikov, the second-ranking military man in the country, and Col.-Gen. Nikolai Chevrov, a senior general staff officer, before foreign and domestic journalists marked an unprecedented break with tradition.

The press conference was apparently intended as a demonstration that the Soviet armed forces are behind the Kremlin's peace drive and that any failure in efforts to renew strategic arms limitation talks should be seen as caused by the policies of the Reagan administration.

While the news conference did not break any new ground, it offered a unique opportunity for assessing two of the top commanders and their grasp of strategic issues.

Varenikov, who appeared to be in his early fifties, is first deputy chief of the Soviet general staff and the principal aide to Marshal Nikolai Ogarkov, the chief of staff and first deputy defense minister. He responded to questions in a cool and detached manner, appearing to be a man of above-average intelligence and self-control who possessed exact mastery of detail.

At one point, Varenikov went out of his way to assert that there has been no difference of opinion between the armed forces and the Soviet political leadership.

Chevrov, who was described as head of a department of the general staff, appeared to be slightly older than Varenikov and somewhat in the mold of the traditional Soviet officer whose basic outlook was shaped by World War II. He spoke with passion and on one occasion mistook the Trident submarine-launched ballistic missile system for the older Poseidon missile system.

The occasion for the press conference was the publication by the Soviet Defense Ministry of a booklet about U.S. military strength.