Former Delaware governor Pierre S. (Pete) du Pont IV said yesterday that the risks in an intermediate-range nuclear forces (INF) agreement with the Soviet Union are greater than generally realized because the overall "strategic balance is infinitely worse today than it was 10 years ago."

The Republican presidential candidate, in an interview with reporters and editors of The Washington Post, said, "We know there are more submarines, more nuclear launchers, more ICBMs" on the Soviet side, adding that he is "skeptical" of those who argue that the balance has improved for the United States.

According to U.S. government statistics, the total number of bombers and intercontinental missiles on both sides has not changed significantly since 1977. Ten years ago the United States had 2,092 and the Soviets had 2,544.

Last year the United States had 1,957 launchers and the Soviets had 2,523.

Du Pont argued that "except for the Strategic Defense Initiative," President Reagan has emphasized a buildup of conventional forces, while the Soviets have continued to "move ahead" on offensive strategic systems.

As disturbing as the INF treaty itself, du Pont said, are the reasons Vice President Bush offered in the Houston debate last week for supporting it. "He said, 'The Joint Chiefs are for it, all the leaders of Europe are for it, Ronald Reagan is for it, and therefore I, George Bush, am for it.' What kind of leadership is that?" du Pont asked. "I don't think we should be for it unless it is right."

Du Pont denied that he has adopted more conservative positions in the campaign than he did as governor or as a member of the House, saying that if he appears to be the furthest right in the GOP field, it is because "my opponents have all moved left."

As he has throughout the campaign, du Pont expressed unconventional views on a variety of economic issues. While others have spoken of an "economic crisis" following the sharp decline in the stock market, he said, "The economy is stronger than it has ever been." The major criteria, he said, are keeping inflation low and providing job opportunities through economic growth, and "on both, Ronald Reagan gets A-plus."

Asked about the large trade deficit -- the gap between imports and exports -- du Pont said, "I don't think it's that much of a worry." He said he opposed any restrictive trade policies that would raise prices or limit freedom of choice for American consumers but supported a strong presidential role in urging other nations to open their markets to American goods.

As for the budget deficit, du Pont said it can and should be trimmed by reducing spending, not raising taxes. A prime target for him would be the $23 billion farm subsidy program, which he argued should be phased out because it has harmed farmers more than it has helped them.

Du Pont also advocated vouchers that families could use for public or private school for their children and a tax-subsidized savings account as an alternative to Social Security. He defended his proposal for random drug testing of youths as a condition for getting a driver's license, calling drugs "a cancer on our society."

"It's the best way I know to send the message that drugs are not acceptable in our society," he said.

Du Pont did not directly assess his chances in the race, but said he would have to do well in Iowa or New Hampshire to continue. "If I should finish fifth in Iowa and fourth in New Hampshire," he said, "the money would stop."