Kathmandu, June 6 -- A sharp rise in bitumen and petroleum prices triggered by the conflict in West Asia has disrupted road construction across Nepal, forcing contractors to halt blacktopping works and delaying several major highway projects.

Contractors say bitumen has become increasingly difficult to obtain, even at higher prices, affecting projects, including the Araniko Highway and Mid-Hill Highway to the Kathmandu-Tarai Expressway and Postal Highway.

Among the worst affected is the expansion of the 15.8-kilometre Sunyabinayak-Dhulikhel section of the Araniko Highway, one of Nepal's busiest road corridors. The project had aimed to complete the first layer of blacktopping across the entire stretch during the current fiscal year.

The...