CALGARY -- AltaGas Ltd. says it has signed a deal to sell its Alaskan utilities business to TriSummit Utilities Inc. for $1.025 billion.

The sale includes Enstar Natural Gas, a gas distribution company in Alaska with about 150,000 customers; the Alaska Pipeline Co., which operates transmission and distribution pipelines for Enstar; the company's 65 per cent indirect interest in Cook Inlet Natural Gas Storage Alaska; and other ancillary operations.

AltaGas says once the deal is complete, its remaining utilities will be concentrated in the Eastern U.S., including Maryland, Virginia, Michigan and the District of Columbia.

The company says the proceeds from the sale will initially be used to reduce debt while providing it with the financial flexibility to advance its growth opportunities.

The deal is subject to customary closing conditions including regulatory approvals.

It is expected to close no later than the first quarter of 2023.