TOKYO - Japanese Prime Minister Shigeru Ishiba said Tuesday that US President Donald Trump's decision to impose a 25 percent tariff on Japan is "truly regrettable," noting bilateral negotiations will continue toward a mutually beneficial deal.

At a tariff task force meeting, Ishiba said the government will not waver in its defense of national interests in future rounds of trade talks, pledging to do all it can to mitigate the impact of the imminent tariff hike on the export-oriented Japanese economy.

"We will continue to engage in negotiations with the United States to explore the possibility of reaching a mutually beneficial deal while protecting our national interests," Ishiba told the meeting.

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Ishiba also said the lack of progress in reaching a trade deal was because "the government has avoided making hasty compromises while demanding and protecting what is needed."

The United States will impose 25 percent tariffs on imports from Japan, beginning Aug 1, Trump said Monday, while warning that any increases to the tariffs on US goods will be met with an equivalent tariff hike by his administration.

The new levy, which is just slightly higher than the 24 percent "reciprocal" tariff announced on April 2, will be imposed separately from sectoral tariffs currently in place, which include a 25 percent duty on vehicles and auto parts and 50 percent duties on steel and aluminum. Trump announced the new tariff rate in a letter to Ishiba released on social media.

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Trump also announced new tariff rates for 13 other countries on the same day, including 25 percent for South Korea, 30 percent for South Africa, 35 percent for Serbia and Bangladesh, 36 percent for Thailand and Cambodia, and 40 percent for Myanmar and Laos.