MAPUTO, MOZAMBIQUE, JULY 31 -- President Joaquim Chissano announced today that his ruling Mozambique Liberation Front would abandon one-party rule and allow a multi-party democracy, a major concession that could help end this nation's long civil war.

The announcement met one of the main demands of the Mozambique National Resistance (Renamo), which has been battling government forces since independence from Portugal 15 years ago. It came as top government and Renamo negotiators were scheduled to begin a new round of peace talks.

While new laws regulating political parties must be approved by the country's legislature before a multi-party system becomes reality, endorsement by the ruling party's top policy-making body appeared to assure the end of one-party rule.

Citing a "new psychological environment" in Mozambique and abroad, Chissano said he was confident that the decision by the party's 12-man Politburo would improve chances to negotiate an end to the civil war.

The conflict has cost an estimated 500,000 lives, left nearly 2 million people on the edge of starvation and brought the economy to the brink of collapse. With an annual per capita income of $150, Mozambique is one of the poorest countries in the world.

Chissano made the announcement after emerging from a Politburo meeting in downtown Maputo, the capital. While a multi-party system would bring "certain dangers" to Mozambique, he said, it was necessary "to safeguard" the interests of the nation.

"The fundamental point is that we believe that no one has the right to deny its citizens who want to form political parties within the law," Chissano said.

The decision was the latest in a series of reforms taken in the last few years by Chissano's ruling party, known as Frelimo, which has ruled Mozambique as the sole legal political party since independence.

Originally a Marxist organization, Frelimo dropped Marxism-Leninism as its official ideology last year, and Chissano said today that the Politburo had begun discussing the need for a multi-party system at that time. Last January, Chissano unveiled a proposed constitution which guaranteed universal suffrage, individual freedoms and the right to own private property.

Today's announcement was timed to coincide with the second round of peace talks between Frelimo and Renamo, scheduled to resume this week in Rome. The first meeting, from June 8-10, was described as a success by both sides.

A multi-party system was Renamo's principal remaining demand following Frelimo's decisions in recent years to embrace a free-market economic program, improve relations with the nation's churches and present a liberal draft constitution.

New political parties cannot legally form until the People's Assembly approves the revamped constitution, a proposed bill for political parties and an electoral law. That is expected to take at least a month.

According to Chissano, Renamo will be able to register as a legal party when the law is changed. "I do not think Renamo would have much trouble registering as a political party," he said. "The law will have no intention of putting up barriers."

But Renamo and other forces are expected to have difficulty setting up party structures across the vast country, about twice the size of California, in time to mount effective campaigns for next year's elections.

Frelimo's acceptance of multi-party rule is likely to have repercussions in the region. Under pressure to follow suit is the socialist government of Angola, which is trying to negotiate an end to a long civil war against guerrillas.