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Parkland Corp.’s Burnaby Refinery on the waters of Burrard Inlet in B.C. Sunoco LP’s bid for the company received a key regulatory approval on Tuesday.DARRYL DYCK/The Canadian Press

U.S. fuel distributor Sunoco LP’s SUN-N proposed takeover of Calgary-based fuel retailer and refiner Parkland Corp. PKI-T has cleared a key regulatory milestone with Ottawa’s approval under the Investment Canada Act.

The transaction is expected to close in the fourth quarter of this year, subject to remaining regulatory approvals and the satisfaction or waiver of customary closing conditions, Parkland said in a release Tuesday.

A review under the Investment Canada Act considers whether foreign investments would be a net benefit to the country or cause potential harm to national security.

The Parkland-Sunoco deal was announced at a time of fraught Canada-U.S. relations and amped-up resource nationalism amid the onslaught of U.S. President Donald Trump’s tariffs.

Earlier this year, Ottawa recently updated national security guidelines under the act to account for potential harms to Canada’s economic security. The government said it will consider the size of the Canadian business, its place in the innovation ecosystem and the impact on Canadian supply chains.

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Parkland and Sunoco announced the friendly cash-and-stock deal valued at US$9.1-billion including assumed debt in May following a bitter proxy battle with investors in the Canadian company unhappy with its performance and strategy.

Parkland owns the Ultramar, Chevron and Pioneer gas station chains as well as several other brands in 26 countries. Sunoco outlets that had long operated in Canada were rebranded in 2009 under the Petro-Canada banner.

Parkland also runs a refinery in Burnaby, B.C., which supplies nearly one-third of the region’s domestically supplied gasoline and jet fuel.

The deal cleared a key U.S. antitrust hurdle last month when the waiting period under the Hart-Scott-Rodino Act expired.

Shareholders approved the takeover in June.