Tokyo Gas Co., Japan's largest city-gas distributor, expects to book an impairment charge of ¥10.6 billion ($90 million) on its U.S. shale gas project and is reviewing its profit forecast following a drop in energy prices.

The company, which last year took a ¥31 billion writedown on U.S. shale and Australia liquefied natural gas projects, plans to disclose any forecast revisions after they are compiled, according to a statement Friday. Tokyo Gas expects net income of ¥122 billion in the financial year ending March, according to an October statement.

The company acquired a 25 percent stake in a shale gas field in Texas' Barnett basin from Quicksilver Resources Inc. in 2013 for $485 million.

Horizontal drilling and hydraulic fracturing has unlocked a flood of natural gas in North America, pushing U.S. prices in December to the lowest since 1999. Oil this week fell to the cheapest in more than a decade.

The price collapse is affecting oil and gas producers, with BHP Billiton Ltd. expecting to book a $4.9 billion writedown on its U.S. shale assets, BP Plc planning to cut 4,000 jobs and Petroleo Brasileiro SA slashing its spending plan.