North korea's economy was severely weakened in the early 1990s when

North korea's economy was severely weakened in the early 1990s when Soviet Union collapsed in 1991, leaving China as the isolated regime's only major ally.

To add, diplomatic relations between the Democratic People's Republic of Korea and the Union of Soviet Socialist Republics (the predecessor state to the Russian Federation) were first established on October 12, 1948 shortly after the Democratic People's Republic of Korea was proclaimed.

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