By Jeff Mason and Leika Kihara WASHINGTON/TOKYO (Reuters) -Powerhouse Asian economies Japan and South Korea said on Tuesday they would try to negotiate with the U.S. to soften the impact of sharply higher tariffs that President Donald Trump now plans to impose from the start of August.

Asian countries including Japan and South Korea said they’ll keep pushing for a better deal for their exports to the US after President Donald Trump shifted his tariff deadline to Aug. 1 and tweaked the rates he’s set for many economies.

Asian shares are mostly down as the Trump administration steps up pressure on trading partners to quickly make new deals before a Wednesday tariff deadline

America is close to clinching several trade deals ahead of a July 9 deadline when higher tariffs were due to kick in, Treasury Secretary Scott Bessent said.

U.S. President Donald Trump on Monday reiterated that countries that don't make trade deals with the United States will get letters, informing them of the tariffs they will be charged if they export products to the United States.

The United States is close to finalizing several trade pacts in coming days and will notify other countries of higher tariff rates by July 9, President Donald Trump said on Sunday, with the higher rates set to take effect on August 1.