Bulgarian President Zhelyu Zhelev pledged yesterday to press for an "independent investigation" into charges that Bulgarian secret police played a role in the 1981 attempt to assassinate Pope John Paul II.

Zhelev, a philosopher who headed the opposition Union of Democratic Forces before his election on Aug. 1 by the Socialist-controlled National Assembly, said his "highly hypothetical" theory is that any Bulgarian role "might have been directed from another country that wanted Bulgarians involved, such as the KGB," the Soviet secret police.

Until now, officials of the Soviet-allied Bulgarian government have denied any connection with Mehmet Ali Agca, the Turkish gunman who wounded the pope in St. Peter's Square on May 13, 1981. Two employees of Bulgaria's embassy in Rome and the deputy manager of the Bulgarian state airline's Rome office were charged with conspiracy in the case, but an Italian court ruled in 1986 that there was not enough evidence to convict them.

Zhelev said that "Bulgaria will seek help from other intelligence services" in probing the papal assassination plot, and "there already have been contacts with the CIA."

The Bulgarian leader, on an unofficial visit to Washington this week, said he personally knew Sergei Antonov, the accused airline official, and had "worked very closely" with Antonov's wife. Zhelev called Antonov "a very decent man" but said it was "very likely that he did some services" for Bulgarian intelligence while living in Italy.

The president declared that if a National Assembly committee launches a formal investigation into the papal plot, "I will take it under my auspices and it will be an independent investigation, because it is in our interest to clear up this case."

In an interview with editors and reporters of The Washington Post, Zhelev spoke strongly in support of the United Nations sanctions against Iraq, calling them "a model of future international cooperation that will provide planetary guarantees for small countries."

Bulgaria, he said, "is among the hardest-hit countries in Europe" from the effects of the Persian Gulf crisis. "We stand to lose $1.4 billion by the end of the year," he said, "most of it in the form of crude oil from Iraq." Iraq had agreed to pay Bulgaria in oil deliveries for arms sold to Baghdad by the previous Communist government in Sofia during Iraq's 1980-88 war with Iran.

"We also were expecting about {14 million barrels} of Iraqi crude from the Soviet Union under contract," Zhelev said.

Bulgaria, which already has stopped payment on a foreign debt of about $10 billion, faces a difficult winter. The country depends on oil imports for about two-thirds of its energy, and its only nuclear power plant is expected to be closed next week because of concerns over its safety.

"We have asked the United States for help," Zhelev said, and Deputy Secretary of State Lawrence S. Eagleburger promised to send 100,000 tons of corn. In a move to break out of its Soviet orbit, Bulgaria became a World Bank member this week.

"We want to improve radically our relations with the United States," said Zhelev, who will meet with President Bush this morning. Zhelev's chief of staff, Ivaylo Trifonov, said the Bulgarian president had invited Eagleburger to send arms experts to dismantle eight SS-23 tactical, short-range ballistic missiles that Sofia had bought from the Soviet Union in 1986 but never armed with nuclear warheads.

Special correspondent Marc Champion contributed to this report from Sofia.