Analysis of information sources in references of the Wikipedia article "Lịch sử Bắc Triều Tiên" in Vietnamese language version.
In fact, as a condition for granting his approval of the invasion, Stalin insisted that Kim get Mao's backing. Kim visited Mao in May of 1950. Mao was inwardly reluctant [...] But with China's Soviet aid at stake, Mao signed on. Only then did Stalin give his final approval.