Shimla, July 16 - Work on the multi-million-rupee Rohtang tunnel project may start next month, aiming to provide an all-weather alternative road connectivity to Ladakh region in Jammu and Kashmir, besides Himachal Pradesh's tribal Lahaul and Spiti district, an official said here Thursday.

'By next month, the sanction to start the excavation work for the strategic Rohtang tunnel is likely to be received from the central government,' Border Roads Organisation (BRO) chief engineer (Project Deepak) I.R. Mathur told IANS.

The BRO, a wing of the central government that constructs and maintains crucial road links along the international borders, has been tasked with the construction of the Rohtang tunnel too.

'The government has earmarked Rs.400 crore for the project for this financial year. An official intimation in this regard has been received by the BRO,' Mathur said.

Last year the central government allocated Rs.200 crore for the project, but the amount lapsed as the government had not granted permission to start the tunnel construction.

The nine-km-long tunnel, foundation of which was laid by former prime minister Atal Bihari Vajpayee in 2002, will reduce the distance between Manali and Leh in Jammu and Kashmir by 40 km, which is otherwise 475 km.

At present, due to heavy snowfall at the Rohtang Pass (13,050 feet), the road connectivity for Lahaul and Spiti and Leh from Himachal Pradesh remains disrupted for more than four months during winter.

The tunnel, some 300 km from here in Kullu district, will be burrowed below the Rohtang Pass so that it avoids the heavy snow.