Chinese president Xi Jinping has reportedly sent a letter to North Korean leader Kim Jong-un reiterating China's steadfast friendship with North Korea. This reaffirms the two nations’ enduring diplomatic relations amidst fluctuating geopolitics. The content of the letter or reasons behind its timing is currently unknown. This event, however, underscores the sustained bond between these two influential leaders in East Asia.

In Japan, the development in China-North Korea relations draw keen attention due to its regional implications and the historical tensions involved. While Japan upholds diplomatic relations with both, it also stands vigilant towards their potential military advancements and human rights situation. The engagement between Xi and Kim can prompt discussions in Japan about their regional diplomacy and national security.

In contrast, the US and EU engage differently with China and North Korea due to their differing historical relationships and views on democracy. Both the US and EU maintain a critical stance towards authoritarian regimes and North Korea’s nuclear program. Consequently, they adopt more stringent measures such as economic sanctions.