They said it would take about two months to repair and mend the national highway at Phesima where about 110-metre portion had sunk because of heavy rainfall for the past few weeks.
An emergency meeting of state government chaired by Chief Minister O Ibobi Singh was held last evening to discuss the situation.
Although no decision was taken, Singh had instructed the authorities to divert the route of these vehicles towards Silchar-Jiribam-Imphal NH-53, sources said.
However, official reports from the districts said the Jiribam route was not still safe even after the repairing of the wooden-bridge at Nungdolan area where the bridge was buried because of landslide about two weeks ago.
Vehicles and trucks have started plying on this route about one week ago but an official report yesterday said pebbles have started falling again piece by piece blocking the route.
Personnel of Border Road Task Force (BRTF) were working round the clock to keep the national highway (Silchar-Jiribam-Imphal) clean 24 hours a day.
Official sources said Union Home Minister of State Jitendra Singh would visit this route and inspect it on July 21.
Official reports from the districts said various social organisations have appealed to the traders and business persons not to increase the prices of essential items taking the advantage of the landslide at the national highway.
Thousands of people at various petrol pumps were seen standing in queue waiting for their turn to get a few litres of petrol for their vehicles in spite of the assurance given by the government that there was enough stock of this at least for four or five days, reports said.
An official spokesman said Chief Minister Ibobi Singh had instructed state DGP to take all security measures to provide vehicles loaded with petroleum products from Khatkhatai in Assam to come to the state via Silchar-Jiribam-Imphal route with immediate effect along with trucks loaded with essential items.