President Donald Trump sent out letters to nations that haven't entered into trade agreements with the U.S., informing them of their new tariff rates.

In letters so far to 14 countries, including smaller exporters to the United States such as Serbia, Thailand and Tunisia, Trump hinted at opportunities for additional negotiations, even while warning that reprisals would draw a like-for-like response.

While South Korean imports to the U.S. face 25% tariffs, the same as Trump promised in April, the rate on Japan has been raised by 1 percentage point to 25%.

Secretary of State Marco Rubio met counterparts in Southeast Asia during his first visit to the region since taking office.

Japan, which Trump said Monday faces a 25% tariff, wants concessions for its large automobile industry and will not sacrifice its agriculture sector for an early deal, top trade negotiator Ryosei Akazawa said.

Imposed 30% tariffs on Libya, Iraq, Sri Lanka, and Algeria. Sri Lanka would continue to engage with the US for a "mutually beneficial" outcome on tariffs, a top finance ministry official said on Thursday, after Washington imposed a 30% tariff on all Sri Lankan imports to the country.

Trump shared screenshots of letters detailing new tariff rates for over a dozen countries, allowing room for further negotiations before the renewed deadline of Aug. 1.

By Susan Heavey, Doina Chiacu and Bart H. Meijer WASHINGTON/BRUSSELS (Reuters) -President Donald Trump said on Monday the U.S. would impose a 25% tariff on imports from Japan and South Korea beginning August 1 as he unveiled the first two of what he has said will be a wave of letters to trading partners outlining the new levies they face.

"America will, once again, build a DOMINANT Copper Industry," Trump said in a post on his Truth Social media platform.

Over the past three months, nations across the world tried to avoid new tariffs that would punish their economies by giving President Donald Trump something he might want. Indonesia offered to buy $34 billion more