Chile received two U.S. warplanes on Tuesday out of 10 it had ordered from the United States as part of a major military upgrade that has worried some of its South American neighbors.

Chile ordered the F-16s in 2002 after the U.S. ended a 20-year ban on the sale of high-tech weaponry to Latin America. The F-16s are not equipped with advanced air-to-air missiles in keeping with a U.S. policy against introducing new military technology to a region. Authorities did not say which missiles the planes carried.

Despite fears from some of Chile's already-weaker neighbors, President Ricardo Lagos insisted that Chile is not altering the region's military balance.

"What we are doing is just replacing material that has completed its useful life," Lagos said at a reception ceremony for the first two fighter planes at a military airport near Santiago.

Rising copper prices have allowed Chile's military to buy expensive new arms, including two submarines made by a Spanish-French consortium, eight secondhand frigates from Britain and Holland, 100 German-made Leopard tanks and 18 secondhand F-16s from the Dutch air force. A law passed during the former military dictatorship of Gen. Augusto Pinochet gives the armed forces 10 percent of Chile's revenue from copper sales abroad.

Chile is the world's largest copper exporter.

While the Chilean government has not disclosed the total cost of its recent military purchases, published reports indicate that the F-16s alone will cost $745 million.

Like the president, Defense Minister Jaime Ravinet tried to reassure Chile's neighbors.

"Chile, unlike others, has no territorial claims whatsoever," he said. "Chile is happy with its borders, and has the obligation to preserve them."

Peru and Chile disagree over their 200-mile border, while many Peruvians and Bolivians still hold a grudge over territory lost to Chile in the 1879-84 War of the Pacific, which ended with Chile victorious over the two countries' joint forces.

Chile is the second South American country to purchase F-16s, after Venezuela.

Peru and Bolivia already have smaller, worse-equipped air forces than Chile's.

Peru's Congress last year passed a law redefining its ocean territory as a first step toward claiming rich fishing grounds currently controlled by Chile.

Chile considers that law a violation of treaties signed with its neighbor.

Air Force Commander Gen. Osvaldo Sarabia, said the F-16s will be stationed in a northern port city that is close to Peru, but he said the proximity had nothing to do with the decision to put them there. Rather, the military airport there is close to the Atacama desert, where flights will not disturb populated areas, he said.