TOKYO: Japan’s trade minister said Thursday he told his US counterpart that sweeping new tariffs including a 24-percent levy on Japanese imports were “extremely regrettable”.

Japanese firms are the biggest investors into the United States but Tokyo has failed in its attempts to secure exemption from US President Donald Trump's tariffs.

“I have conveyed that the unilateral tariff measures taken by the United States are extremely regrettable, and I have again strongly urged (Washington) not to apply them to Japan,“ Yoji Muto, trade and industry minister, told reporters.

He said he made the comments in a conversation with US Commerce Secretary Howard Lutnick before Trump's announcement of new across-the-board tariffs.

“I also explained in detail how the US tariffs would adversely affect the US economy by undermining the capacity of Japanese companies to invest in the United States,“ said Muto.

“We had a frank discussion on how to pursue cooperation in the interest of both Japan and the United States that does not rely on tariffs,“ Muto said.

Government spokesman Yoshimasa Hayashi also said that the measures may contravene World Trade Organization (WTO) rules and the two countries' trade treaty.

“We have serious concerns as to consistency with the WTO agreement and Japan-US trade agreement,“ chief cabinet secretary Hayashi told reporters.

In February, Trump hosted Prime Minister Shigeru Ishiba for apparently friendly and fruitful talks, with a joint statement hailing a “new golden age for US-Japan relations”.

Japan has also failed to win exclusion from 25-percent tariffs on auto imports due to come into force later Thursday.

Last year, vehicles accounted for around 28 percent of Japan's 21.3 trillion yen ($142 billion) of US-bound exports, and roughly eight percent of all Japanese jobs are tied to the sector.