Maoist leaders at a jan-adalat (kangaroo court), held at a dense forest in Gaya district, about 100 km from here, issued the diktat, police said.
They warned Choudhary not to organise programmes for distribution of the Indira Awas Yojna funds and also objected to his initiatives for construction of roads and bridges in the area.
The threat came after Maoists released Lakhan Lal Vermn, an abducted aide of Choudhary, late Friday. Vermn, who was thrashed at the jan-adalat, was abducted from Maigra bazaar Thursday by Maoists for illegally capturing the land of poor people, police said.
However, opposition leaders allege that Choudhary has good relations with Maoists, who have been helping him in the campaigning. Imamganj is considered a stronghold of Maoists.
Choudhary is the first Dalit speaker of the Bihar assembly.