Any deal will likely be favorable to the Russians, though the clock on Putin’s ability to sustain a wartime economy may be running out.

Ukraine’s use of long-range missiles to attack Russia comes as both sides are positioning for peace talks once Donald Trump becomes president.

Ukrainian and South Korean intelligence services have said that many of the troops deployed to Russia are some of Pyongyang’s best, drawn from the 11th Corps, also known as the Storm Corps - a unit trained in infiltration, infrastructure sabotage and assassinations.

Western and Ukrainian officials have called the appearance of North Korean forces on the battlefield a major escalation.