Taiwan's former president, Lee Teng-hui, said yesterday that a growing military imbalance with China has made it increasingly necessary for the island to acquire "some kind of long-range missiles" that would give it an offensive capability.

"The psychological effect is important" in order to deter China from attacking Taiwan, Lee said in an interview during a tour this week of the United States. Lee's remarks, made as Defense Secretary Donald H. Rumsfeld was on his first official trip to China, could be seen as provocative by the government in Beijing, which regards Taiwan as a renegade province.

The Bush administration has pushed Taiwan to buy defensive weaponry, but Lee said the package under consideration would leave Taiwan shortchanged. A purely defensive posture, he said, "is a very big risk to the military balance across the Taiwan Strait."

China has more than 700 ballistic missiles pointed at Taiwan, and much of China's military buildup appears aimed at achieving air and sea superiority in any conflict with the island nation.

Last month, however, Taiwan's two main opposition parties blocked a $10 billion arms purchase from the United States even though the ruling party has scaled back the cost. The arms bill would fund the purchase of eight conventional submarines and 12 P-3C Orion submarine-hunting aircraft.

Lee, 82, who was president from 1988 to 2000, is a fervent advocate of Taiwanese independence. He is the spiritual leader of the Taiwan Solidarity Union, which is allied with President Chen Shui-bian's ruling party.

Beijing has formally protested Lee's visit as damaging to U.S.-China ties. Lee is meeting with congressional officials and making speeches but is not meeting with administration officials. The Bush administration has declined to comment on his trip, saying it is a private visit.

Lee, who addressed more than 1,000 supporters in New York on Sunday, is to give a speech at the National Press Club tomorrow.

During his trip, Lee is promoting a pro-independence movement, focusing on creating what he calls a "national identity" for Taiwan. Shortly after arriving in Washington, he visited the National Archives to view the Declaration of Independence.

"Taiwan is already an independent country," Lee said in the interview. What is needed now, he said, is for the formal name, Republic of China, to be dropped in favor of the reality, the Republic of Taiwan. The formal name dates to 1949, when the Nationalist government was defeated by the Communists on the mainland and established itself on Taiwan.

China has said such a move would lead to war, and the Bush administration has pressured Chen to tone down his rhetoric to avoid upsetting the status quo.

The United States long has maintained a "one-China" policy -- saying both sides believe Taiwan is part of China -- while supporting Taiwan with arms sales. But the one-China policy has been a difficult diplomatic fudge to maintain as Taiwan has become a thriving democracy.

China shifted its tone on Taiwan this year and welcomed two of Chen's political rivals to the mainland. Lee criticized the visits and said the Taiwanese needed to join together to promote their nation's identity to counter China's lure.