NEW DELHI, FEB. 9 -- U.N. special negotiator Diego Cordovez announced today in Islamabad that negotiations between Pakistan and Afghanistan on a settlement of the Afghan war will resume in Geneva on March 2.

The announcement followed by a day Soviet leader Mikhail Gorbachev's declaration that his troops would begin leaving Afghanistan on May 15, provided a peace settlement was reached by mid-March.

Cordovez said that his latest round of 21 days of shuttle diplomacy had led to "virtual agreement" on almost all aspects of a Soviet troop withdrawal and a guarantee of noninterference in the internal affairs of Afghanistan, according to reports from the Pakistani capital. Cordovez, an undersecretary general of the United Nations, left for Geneva and New York after a final courtesy call on Pakistani leaders.

Pakistani Deputy Foreign Minister Zain Noorani said late today in Islamabad that Pakistan welcomed Gorbachev's statement and that Islamabad is "now prepared to intensify . . . efforts to reach a comprehensive settlement."

Noorani, however, underscored Pakistan's insistence on reaching an understanding on a new government to replace the communist regime in Kabul, something Gorbachev said in his statement last night that Moscow wanted no part of.

A "legitimate, responsible, broad-based government," is an "indispensible aspect" of any settlement of Afghanistan's eight years of warfare, the Pakistani official said.

Talks in Islamabad involving Soviet First Deputy Foreign Minister Yuri Vorontsov and top Pakistani officials are scheduled to begin Wednesday and many observers say their outcome could provide the answer to the degree of cooperation that can be expected in coming weeks between these major actors in Afghan affairs.

The Soviet Union has an estimated 115,000 to 120,000 troops in Afghanistan and is the mainstay of the government of President Najibullah. Although Pakistan publicly denies the role, it serves as the funnel for massive military supplies, provided mostly by the United States, for Afghan anticommunist guerrillas. Those forces have sanctuary in Pakistan, along with an estimated 3 million Afghan refugees.

Gorbachev, in reducing by two months the period of the proposed troop pullout, and in saying the majority of the troops could be withdrawn in the early stages, addressed two of the major remaining issues.

Cordovez appeared to have resumed his more optimistic attitude toward a possible settlement, saying that all that is left is "to work out logistical, technical and practical" details of an agreement. He stressed, however, that "there still is a considerable amount of distrust on both sides."

Under the proposed U.N.-negotiated Geneva accord on the war, the Soviet Union would agree to withdraw its troops and the United States and Pakistan would end military support for the Afghan resistance.

Afghanistan would become a nonaligned state protected from outside interference, an aspect of the accord that would be guaranteed by the United States and the Soviet Union. Refugees would return.

The accords would be signed by Pakistan and Afghanistan, which have been negotiating for nearly six years. But Pakistan has thrown into doubt whether it will sign an agreement with a government headed by Najibullah or any other leader of the communist People's Democratic Party of Afghanistan.

President Mohammed Zia ul-Haq said last month that he would not sign an accord with Najibullah's government, which he said he did not consider to be "legitimate." Noorani repeated those sentiments today, saying that Pakistan would sign an accord with the "legitimate government of Afghanistan as and when the time for signing comes."

"There are two tracks left -- Geneva and the transitional government. Both of these have got to converge . . . at one stage or another," Noorani said, leaving open whether this convergence would come before the talks.

Under the Geneva procedure, an agreement could be reached in the round that is to begin March 2, but it would not be signed for another 60 days, when its provisions -- including the start of troop withdrawal -- would come into effect.

Gorbachev said yesterday that Moscow no longer is insisting on linkage between a troop withdrawal and the type of government that could emerge in Kabul.

The establishment of a coalition government "is purely an internal Afghan issue. It can only be resolved by the Afghans themselves, although they belong to different and even opposing camps. When, however, it is hinted to us that the Soviet Union should take part in talks on that issue, and even talk to third countries, our answer is firm and clear: Don't expect us to do it; it is none of our business," the Soviet leader said.

Pakistan, on the other hand, is said to believe that some type of agreement on a new government is essential to win the cooperation of the resistance troops based in Pakistan. Without this cooperation, some Pakistani officials are said to fear that they would be left with large numbers of armed guerrillas and refugees on their soil.

Other Pakistanis are said to be pressing this issue because they want to ensure a government in Kabul with which they would have long-term influence, providing a degree of security on their turbulent frontier.

Cordovez said that there is a consensus that a broader government in Kabul would make it easier to implement an accord but that there are "no formal linkages of any kind."

"People just do not believe these agreements are going to be concluded. When Afghans see there is at Geneva a very firm, a very specific, a very solid agreement on withdrawal, attitudes will change," Cordovez said.