To reengage with the international community, and to deal with the economic challenges brought by the changes in the Soviet Union and Eastern Europe, Vietnamese leaders decided to embark on a series of reforms. At the 6th National Party Congress in December 1986, newly appointed General Secretary of the VCP Nguyen Van Linh introduced a major reform known as Đổi Mới, the Vietnamese term for "renovation", in order to fix Vietnam's economic problems. However, Vietnamese leaders concluded that Vietnam's dire economic situation came as a result of the international isolation which followed its invasion of Kampuchea in 1978, and that for Đổi Mới to be successful it needed radical changes in defence and foreign policy. Subsequently, in June 1987, the Vietnamese Politburo adopted a new defence strategy in Resolution No. 2, calling for the complete withdrawal of Vietnamese soldiers from international duties, a reduction in the size of the army through a discharge of 600,000 soldiers and the establishment of a set ratio for military expenditures.