Silchar-Lumding Broad Gauge Rupayan Sangram Committee (SLBGRC) said that the project is "unlikely to be completed by the target date of December 2013."
"The work is progressing at a very slow pace everywhere. No work is going on at the Banderkhal area, where construction of a long bridge has been half completed," SLBGRC secretary Ajoy Roy said.
Former Prime Minister H D Deve Gowda had inaugurated the Silchar Lumding broad-gauge project in 1996.
Former MLA Misson Ranjan Das said that government often cite the militancy related problems as an excuse for the tardy pace of work.
"However, Assam is a much safer place in comparison to Tripura and Jammu and Kashmir which are both having broad gauge of their own," he added.
All India United Democratic Front leader and MLA in state assembly Ataur Rahaman Majarbhuiya said that government's other excuse about poor condition of roads in the area hampering transport of construction materials does not sound good.
"A national project is being delayed due to the bad road condition. Such excuse seems not fit at all. Why the roads have not been repaired over the years," Majarbhuiya said.
He said the delay has resulted in escalation of the project cost to Rs 3,909 crore from the original Rs 1,689 crore and added that any more delay will only increase the cost further.