The Japanese Government's decision to issue... [the] visa is a major breakthrough

Vice-President Annette Lu

Ms Lu also said Taiwan, Japan and South Korea should form an alliance to promote peace and stability in the region.

Former President Lee arrived in Japan on Monday for medical treatment after Japan granted him a visa on the condition he does not engage in political activity.

Ms Lu's comments are likely to provoke an angry response from Beijing, which views Taiwan as a breakaway province that must be reunited with the mainland.

'Good feeling'

In Japan, the government's top spokesman has said he hoped Mr Lee would focus on his heart treatment while in Japan.

Ms Lu is reviled in Beijing for her independence views

"Now that he has come here, we would hope he focuses on his treatment and breathes a lot of Japanese air and returns... with a good feeling," about Japan, Chief Cabinet Secretary Yasuo Fukuda said on Monday.

Mr Lee, 78, will see a heart surgeon in a hospital in Kurashiki, western Japan, for a follow-up after surgery he underwent last November in Taipei.

An outspoken critic of Beijing, he has so far kept his trip low profile although local media have hailed Japan's decision to grant him a visa as a diplomatic victory over China.

China warns US

China, which has tried to push Taiwan into diplomatic isolation, had warned Tokyo not to issue a visa to Mr Lee.

US-China relations are already frayed over the spy plane crisis

It has also protested to the United States, which has given Mr Lee a visa for a trip there.

The US decision to allow Mr Lee to visit from 30 April to 6 May has pitched relations between the two countries into a new crisis.

A foreign ministry spokesman, Zhu Bangzao, urged Washington to "correct its mistakes" to prevent further damage to relations between the two countries, already hurt by the US spy plane row.

He said Mr Lee's attempt to visit the US as a tourist was simply a cover for his political aims and would boost attempts to split China.

Beijing has also said there could be devastating consequences for bilateral ties if President George Bush decides this week to sell advanced missile defence systems to Taiwan.