Asian stock markets fell on March 23 as tensions in the Middle East rose over U.S. President Donald Trump's "ultimatum".

According to Bloomberg, Japan's Nikkei 225 was down 3.92 percent at 10:26 a.m. Korea time from the previous session.

South Korea's KOSPI stood at 5,522.07 at 10:41 a.m., down 4.48 percent from the previous trading day.

The KOSDAQ was down 3.34 percent at 1,122.77 at the same time.

Taiwan's Taiex index fell in the 2 percent range.

China's Shanghai Composite, Shenzhen Composite and Hong Kong's Hang Seng Index were also down in the 1 to 2 percent range.

Earlier, Trump warned on March 21 on social media platform Truth Social that he would devastate Iran's power facilities unless the Strait of Hormuz was fully reopened within 48 hours, and Iran is pushing back by saying it will step up the intensity of its blockade of the strait.

According to Britain's Guardian newspaper, the deadline for Trump's ultimatum is understood to be around 8:44 a.m. Korea time on March 24.

International oil prices are also swinging due to the fallout from a "hardline against hardline" confrontation. Brent crude futures, a global benchmark, surged to as high as $114.35 a barrel at 7 a.m. Korea time on March 23 before easing slightly to the $111 range.

U.S. West Texas Intermediate futures also rose to $101.50 at the same time before falling back to the $98 range.

In the industry, many see major volatility continuing in the global oil market for some time, given the low likelihood that Iran will accept Trump's demands.

[Yonhap News Agency]