HANOI, Nov 23 (Reuters) - Vietnam's president, Vo Van Thuong, will visit Japan next week, a Vietnamese foreign ministry spokesperson said on Thursday, as the two countries discuss strengthening their relations.

Closer ties would confirm Vietnam's increasingly strategic role as an important link in global supply chains amid trade tension between China and the West, which is helping to bring foreign investment to the southeast Asian country as some companies relocate operations from China.

The elevation of ties with Japan would follow Vietnam's historic upgrade of relations with the United States in September, when the former foes signed multiple cooperation agreements, including on semiconductors and critical minerals.

It may also be followed by a visit to Hanoi by China's President Xi Jinping, who according to officials and diplomats, could travel to Vietnam in December and agree on a joint statement indicating the two countries share a common destiny.

Thuong's visit from Monday to Thursday next week is his first to Japan as president and coincides with celebrations for the 50th anniversary of ties between the Asian countries.

Vietnam classifies Japan as a strategic partner, one notch below China, Russia, South Korea, India and the United States.

Japan is Vietnam's third-largest source of foreign investment and its fourth-largest trading partner.

Several Japanese multinationals have big factories in the southeast Asian manufacturing hub, including Canon, Honda, Panasonic and Bridgestone.

Talks about a possible diplomatic upgrade have been going on for months with officials discussing possible cooperation agreements, diplomats said.

It is not clear whether an upgrade would be announced during Thuong's visit or later.

"The visit will contribute to deepening relations between the two countries in trade, investment and the economy," Vietnam's foreign ministry spokesperson told a press conference, declining to comment about a possible upgrade.

(Reporting by Khanh Vu and Francesco Guarascio; editing by Robert Birsel)