Conflict has ensued among the members of the Nepal Student Union (NSU) regarding the appointment of convention representatives for the ongoing 10th convention in Chitwan.
The closed session has been stalled on Tuesday after the opposition groups demanded final list of the convention representatives.
The opposition groups accused the establishment of including over 200 additional students to win votes in the election.
The student leaders had earlier agreed that no students from +2 would be entertained in the convention. But the opposition groups say more than two dozen such students have been brought to the convention.
Over 1,400 students are attending the 10th convention of the NSU from 75 districts against the quota for 1,200 students.
The opposition groups have said they will not allow the proceedings of the closed session until the problem is resolved.
The NSU convention had abruptly stalled due to conflict among the student leaders in Pokhara last year.
Vice president of the Nepali Congress Shushil Koirala, who was in Chitwan on Monday to inaugurate the convention and solve the dispute, is already back to Kathmandu.