North Korea has indicated that it might continue its nuclear testing in response to the U.S. and South Korea continuing their military partnership.
Here's what we know
According to the Washington Post, North Korea's Foreign Ministry said that its decision to not conduct nuclear tests was "not a legal document inscribed on paper."
It added, "With the U.S. unilaterally reneging on its commitments, we are gradually losing our justification to follow through on the commitments we made with the U.S."
The U.S. and South Korea scaled down their previous joint military drills and war games in 2018 in order to avoid aggravating North Korea. However, the two countries have continued their close partnership, as they have since the end of major hostilities in the Korean War.
North Korea has long viewed these drills as an act of aggression. In March 2015, a spokesman for the North Korean People's Army general staff said that the joint exercises by the U.S. and South Korea were proof that "the situation on the Korean Peninsula is again inching close to the brink of war" and that the only way to deal with "the aggression and war by the U.S. imperialists and their followers is neither dialogue nor peace. They should be dealt with only by merciless strikes."
There have also been numerous reports that North Korea has continued to develop its nuclear program.
Trump said in December that the U.S. was "in no hurry" to reach a deal with North Korea.
North Korea has a track record of promising to denuclearize and then going back on that promise. It has done this at least six separate occasions: in 1985, 1992, 1994, 2005, 2007, and 2012.