Japan’s economy risks taking another hit if US President Donald Trump slaps fresh tariffs on China, sparking a renewed US-China trade war, according the government’s chief economist.

Policymakers, investors and economists are watching Trump’s trade policy amid fears that his threatened use of tariffs could batter global commerce.

Japanese companies remain bullish about investing in the United States but need to prepare for supply chain shocks that could arise during Donald Trump's presidency, the chief executive of drinks giant Suntory Holdings said on Wednesday.

Japan intends to closely monitor the impact on its currency of US President Donald Trump’s new tariffs and is worried about the international fallout from the trade imposts, Finance Minister Katsunobu Kato said.

As President Donald Trump threatens to impose his first tranche of tariffs on the world Saturday, Chinese manufacturers are bracing for impact.