A U.S. State Department spokesperson said Thursday that North Korea's involvement in Russia's war against Ukraine causes "great concern" and "consternation" for the Indo-Pacific.

The U.S. says there will be a "firm response" as Ukrainian forces holding ground in Russia's Kursk region now face North Korean troops "engaging in combat."

SEOUL, South Korea (AP) — North Korea ratified a major defense treaty with Russia stipulating mutual military aid, the North’s state media reported Tuesday, as the U.S., South Korea and Ukraine say North Korea has sent thousands of troops to Russia to support its war against Ukraine.

A photo has emerged showing examples of a North Korean-made self-propelled artillery system under transport in Russia, the clearest suggestion so far that Pyongyang is also now providing Moscow with these kinds of heavyweight,

Ukraine’s allies will look to pressure China over North Korea’s growing support for Russia’s war during a Group of 20 Summit in Brazil, according to people familiar with the matter.

Russian soldiers have been filmed giving North Korean troops battlefield training and language lessons, with some of Kim Jong-un’s men picking up swear words.

"Today I can confirm that over 10,000 (North Korean) soldiers have been sent to eastern Russia, and most of them have moved to the far western Kursk Oblast, where they have begun engaging in combat operations with Russian forces,

Photos have begun to appear on Russian social media showing the transport of North Korean long-range artillery systems that have been delivered to Russia. According to Defence Blog, these include the M1989 "Koksan",