The Covid-19 pandemic has inflicted increased construction costs and delay on Coastal GasLink, the conduit designed to supply the Royal Dutch Shell plc-led liquefied natural gas (LNG) export project underway in British Columbia (BC), according to TC Energy Corp.

“We expect project costs will increase significantly and the schedule will be delayed,” TC management said Thursday in its 2020 year-end statement. “Coastal GasLink will continue to mitigate these impacts to the extent possible.”

Provincial virus control restrictions on industrial labor forces, ordered at the end of December, foiled a TC forecast last November that the 670-kilometer (400-mile) line would be completed across northern BC in 2023 for C$6.6 billion ($5 billion).

A revised construction cost and...