President Joe Biden, on his way out of the White House, has left President-elect Donald Trump a “parting gift” — an escalation of the war between Ukraine and Russia.

Late last week, Biden inexplicably ‘authorized’ Ukraine to utilize long-range U.S. weapons for strikes on Russian soil, which was meant by a reminder from President Vladimir Putin that any escalation could force Moscow to deploy nuclear weapons, even if on a limited basis.

Biden’s authorization comes after reports earlier in the month said that North Korea had sent approximately 10,000 troops to Russia in preparation for introducing them into combat in Ukraine.

Administration officials hinted in May that the president could reverse course and authorize Ukrainian forces to use American-made and supplied weapons for strikes into Russia, but nothing developed over the course of the presidential election cycle. After Trump won, however, Biden changed his mind and gave the incoming administration a bigger problem.

The missiles, The Wall Street Journal reported, “could initially target positions in the Kursk region, where Russia has amassed more than 50,000 troops, including some 10,000 soldiers from North Korea, in an effort to recapture the territory.”