He drafted left-wing politicians, including Hou Yuon, Hu Nim, and Chau Seng, to stand as Sangkum candidates, with a view to winning left-wing support from the Pracheachon.
The situation was inflamed in March April 1967 by a revolt in the far north-east of the country, the Samlaut Uprising, that was blamed by Sihanouk on left-wing agitation, and specifically, though most likely incorrectly, on the activities of the remaining openly leftist politicians : Hou Yuon, Khieu Samphan, Chau Seng and Hu Nim.