The US military has announced that its forces are tied up elsewhere because of the situation in the Middle East, a South Korean navy spokesperson said at a press conference.
Another exercise that the countries held jointly last week was scaled down on the orders of US President Donald Trump, who cited costs and South Korea's reluctance to participate in the US war against Iran.
At the time, Trump also described the exercises as inappropriate and hostile, while speaking warmly of South Korea's arch-enemy North Korea and its dictator Kim Jong-Un.
The exercise that was supposed to be held in September is called Ssangyong and has been held every two years since 2012.
