The social organisations have been organising sit-ins at various parts of the valley since the past two weeks.
The demonstrations were held in major places like Imphal market complex, Pishum, Wangkhei, Sagolband, Singjamei and Uripok among others, officials said.
Ruling Congress legislature party members had held two meetings in the past five days to discuss introduction of a bill in the current session of the assembly for implementation of the ILPS but the meetings could not take any decision as some members wanted an opinion from the Home ministry.
"It is in the hands of the state government and there is no point seeking opinion from the Union Home ministry," said noted lawyer and former district sessions judge C Upendra Singh.
A spokesman of the Federation of Regional Indigenous Society (FRIENDS), a participant in the fast, said labourers, daily wage earners and businessmen who have entered Manipur in the past some decades have outnumbered the total tribal population in the hill districts.