A strategic highway tunnel in the Himalayas near India's border with China was inaugurated on Saturday by Prime Minister Narendra Modi.
The opening of the tunnel comes amid a stand-off between the nuclear-armed Asian neighbours along a disputed border in the eastern Ladakh region.
The 9.02-kilometre tunnel will provide year-round access by road to Ladakh from the rest of India.
The region usually remains cut off for six months of the year, when the two Himalayan passes providing access are blocked by snow.
"The Atal tunnel will give new strength to India's border infrastructure," Modi said at the inauguration.
He added the all-weather tunnel would be a lifeline for people in the Ladakh region.
The tunnel has been more than 20 years in the making and is named after former prime minister Atal Bihari Vajpayee, who laid the foundation stone of the project in 2002.
The tunnel, built over 3,000 metres above sea level, would reduce the travel time between Manali in Himachal Pradesh and Ladakh's main city, Leh, by four to five hours, the prime minister's office said.
The tunnel will also allow supplies to reach troops stationed along the line of actual control with China, a disputed informal border, throughout the year.
India and China are currently engaged in talks for scaling down tensions and drawing back of troops in the region.
