Kim Jong Un
Some 10,000 fighters are believed to have been sent to the region.
North Korea and Russia signed a mutual defence pact earlier this year.
South Korea's defence minister warned there's a strong possibility Russia is taking soldiers from the Asian dictatorship.
"Good on you, Donald..."
Was it excessive politeness or political symbolism?
Coming from two authoritarian leaders, that's quite the promise.
The former president's boast isn't sitting well with his critics.
The presidents' meeting has caused concern that they're considering an arms deal.
Includes claims about Trump and British-trained Ukrainian "saboteurs".
And why would a meeting offer a boost for both the Russian leader and his North Korean counterpart?