Prime Minister Dr Mahathir Mohamad, fresh from a trip to the United States, will leave today for a four-day visit to Japan and South Korea.

The 75-year-old veteran Southeast Asian leader is to deliver a keynote address at the eighth Nikkei International Conference in Tokyo.

He is also scheduled to meet Japanese Prime Minister Junichiro Koizumi and other Japanese ministers, the foreign ministry said in a statement issued to Bernama news agency.

Mahathir will also travel to Nagasaki for the Malaysia International Shipping Corporation's ship-naming ceremony.

He leaves Wednesday for a two-day visit to South Korea, his first in 12 years, at the invitation of President Kim Dae-Jung. The visit was aimed at boosting bilateral ties and to build a closer rapport between the leaders.

It will be Mahathir's third visit to South Korea.

Mahathir and Kim are expected to hold a restricted meeting to discuss bilateral, regional and international issues of mutual interest, the foreign ministry statement said.

The two leaders will witness the signing of five memorandums of understanding. No details were available.

Mahathir will also speak at a business luncheon and visit Hyundai Motor Research and Development, LG Chemical Investment and Satellite Technology Research Centre Initiative.

He will be accompanied by Foreign Minister Syed Hamid Albar, Trade Minister Rafidah Aziz, Energy, Communications and Multimedia Minister Leo Moggie and other senior officials.