Shimla, March 3 (IANS) The snow clearing work on the strategic 475-km National Highway-21 that connects Manali in Himachal Pradesh to Leh in Jammu and Kashmir has started, an official said Wednesday.

The highway has been closed since Dec 10 last year after heavy snowfall.

'The snow clearing work on the Manali-Leh highway started yesterday (Tuesday) from Gulaba near Manali,' S.K. Doon, Commander of General Reserve Engineering Force's (GREF) 38 Task Force, told IANS.

The GREF is a wing of the Border Roads Organisation (BRO) that maintains the highway.

'We are trying to re-open the Rohtang Pass, the gateway to Lahaul and Spiti district, by mid-April. But this depends upon weather conditions,' he said, adding the road to Kothi, 13 km from Manali, has been re-opened to traffic already.

The majestic Rohtang Pass is located 52 km from Manali.

An official of the BRO said the entire stretch of the road between Manali and Leh would be re-opened to traffic by the end of May.

The Manali-Leh highway passes through rugged terrain.

The highway plays an important role in the movement of armed forces to the border areas in Ladakh.