ROME, NOV. 18 -- Soviet President Mikhail Gorbachev signed a nonaggression treaty with Italy today and won another parcel of Western aid for his struggling economy.

Italian Prime Minister Giulio Andreotti said a $900 million credit line for Moscow was "the first in a series." The Italian government assembled a $6 billion package for Moscow last month, although the cash-strapped Italian Treasury complained that it did not have the money.

Italian officials had said as late as Friday that economic accords signed today -- but not made public -- would cover this. Andreotti's statement indicated that the rest of the package would be announced bit by bit.

Gorbachev said during his nine-hour stop here that "there are new ideas that need to be examined" that could lead to a peaceful resolution of the Persian Gulf crisis. Gorbachev did not elaborate on the new ideas, although he insisted that a solution must involve the United Nations and the Arab states. His spokesman, Vitaly Ignatenko, said Gorbachev had discussed the ideas privately with Andreotti.

Ignatenko said Gorbachev stressed that the United Nations "still has the chance to increase the pressure on Saddam Hussein." Andreotti's spokesman, Pio Mastrobouoni, said the two leaders agreed that efforts to avoid a military conflict in the gulf must continue.

The Soviet leader also met with Pope John Paul II, renewing his invitation for the Polish-born pontiff to visit the Soviet Union. The pope told reporters he hoped to go but did not commit himself to a date.

Vatican officials said such a trip would not be possible before 1992, stressing that the Vatican first needs to assess the number of faithful and clergy and the overall state of the church in the Soviet Union.