Rohtang Pass is the gateway to Keylong in the landlocked Lahaul Valley from Manali in the state's Kullu district. It remains off-limits from the rest of the country for over five months due to heavy snow deposits on the road.
"From Nov 15 onwards, we will officially close the Rohtang Pass. We will also withdraw most of the state-run buses between Manali and Keylong," Deputy Commissioner B.S. Thakur told IANS over phone.
He said only emergency vehicles would be allowed to ply till the onset of heavy snowfall.
Official sources said the Border Roads Organisation, which maintains the highway that passes through rugged Himalayan ranges, has informed the state government that it would not be in a position to operate the highway after Nov 15.
It will withdraw its men and machinery deployed at various locations along the highway with the onset of snowfall.
The pass, located at an altitude of 13,050 ft and 51 km from here, experienced mild snow Wednesday.
Thakur said the government would set up rescue posts on both sides of Rohtang Pass by Nov 15.
The weather at Rohtang Pass is harsh. A sudden drop in the temperature, even in summer, can trigger winter-like conditions.