The proposed strategic arms limitation treaty (SALT) with the Soviet Union fails to reduce the risk of a surprise attack on the United States, Paul H. Nitze said last night.

In a speech before the Chicago Council on Foreign Relations, Nitze said that by the early 1980s the Soviet Union "may be in a position to destroy 90 percent of our ICBMs" by firing only one-third of its missiles.

Even if U.S. bombers and submarines survived such an attack, Nitze said, they would be no match for the arsenal the Soviets would have left after launching the first strike.

Nitze, a former deputy secretary of defense who is now an executive of a defense-minded group called the Committee on the Present Danger, said the increased temptation to strike first is "the most worrisome" casualty suffered during U.S.-Soviet arms control negotiations.

Under the proposed agreement, known as SALT II n/itze said "it will be impossible" for the United States to build up its force of multiple-warhead intercontinental ballistic missiles to the allowed limit of 820 by 1985, the year the treaty would expire.

In contrast, he said, the Soviets "almost certainly" will have deployed 820 missiles -- thus enjoying a significant edge when calculating the advantages and disadvantages of a first strike.

Nitze also cited what he considered other Soviet advantages in the proposed treaty, including being allowed more warheads for its individual land missiles than the United States will deploy and having its Backfire bomber force exempted in counting strategic weapons.

If the SALT II agreement is signed by President Carter and submitted to the Senate next year, Nitze is expected to be a leading critic in the debate over whether it should be ratified.