THIS month, the Senate Foreign Relations Committee will consider the president's foreign aid request for fiscal year 1992. Regrettably, the president's package deletes an important nuclear-nonproliferation provision that affects Pakistan. In the wake of the Persian Gulf conflict, there is little support in Congress for proposals to weaken existing nonproliferation laws.Under current law, all foreign assistance to Pakistan is prohibited unless the president certifies to Congress that Pakistan does not possess a nuclear weapon. This fiscal year, the president has not been able to make that certification. Consequently, all economic and military assistance to Pakistan is on hold. This nuclear-nonproliferation provision is known as the "Pressler Amendment." When I offered it in 1985, some senators sought to curtail all United States assistance to Pakistan. At the time, however, Pakistan had 120,000 Soviet troops on its border, and it was experiencing cross-border raids from Afghanistan and wanton acts of Soviet-inspired terrorism in the crowded bazaars of Peshawar and Islamabad. A draconian cut in foreign assistance to Pakistan at that time would have undermined the security inter ests of both Pakistan and the US. Nonetheless, I believed it was important to send a strong message of our concern to Pakistan. I offered a compromise amendment, endorsed by President Reagan, to establish a clear policy on assistance to Pakistan. That standard merely requires the president to certify that Pakistan does not possess a nuclear weapon. With that certification, generous levels of economic and military assistance are available. Indeed, since my amendment was adopted, every year Congress has supported the president's request for both security assistance and economic assistance. Until last October, Pakistan was among the largest recipients of US foreign assistance. So there should be no doubt in the mind of any Pakistani about the American commitment to help. The amendment sets a fair standard. It has been on the books now for six years. Pakistani officials have been reminded of it time and again by senior US officials. We do not know for certain whether Pakistan possesses a nuclear weapon. But the president has not certified that Pakistan does not possess such a weapon or the components to assemble one. PRESIDENT Bush's proposal to strike my amendment does not appear to stem from a disagreement between Congress and the administration. In an April 12 letter the president stated: "While the proposed elimination of the Pakistan-specific certification requirement is intended to uphold the general principle of presidential authority, I will continue to insist on unambiguous specific steps by Pakistan in meeting nonproliferation standards, including those specifically reflected in the omitted language known a s the Pressler Amendment." The bonds of friendship between Pakistan and the US are highly valuable. Pakistan stood stalwartly with the Afghan freedom fighters after the brutal Soviet invasion of 1979. It has sheltered the largest refugee population in the world. During the recent Persian Gulf crisis, Pakistan's government stood courageously with the US - despite contrary pressure from powerful elements of the Pakistani military. It is in both our interests to move beyond this impasse. Eliminating the Pressler Amendment won't solve the problem. The events of the past year show that Congress must be more vigilant than ever on matters of weapons proliferation. While President Bush has pledged to hold Pakistan to the "Pressler standard," I believe that it is important for Congress to express an unequivocal view on this issue. As Congress considers the administration's new foreign-aid proposals, I will oppose any effort to eliminate the nuclear-nonproliferation provision.