If a U.S. wind-power company has its way, the federal government could end up footing the bill for part of a costly and controversial Ontario energy initiative. The case could renew the conversation around international business conflicts at a time when two major trade pacts are awaiting ratification in Canada.

Windstream Energy, based in New York state, won a contract in 2010 to build 100 offshore wind turbines near Kingston. But less than a year later, the Ontario government halted all offshore wind-power development, claiming it needed more time to study the potential risks of such projects.

The company says the provincial government acted in “an arbitrary and political manner.” Rather than pursuing its case with the province however, Windstream is demanding $475 million from the federal government under a provision of the North American Free Trade Agreement that allows companies to sue Canada over government measures that interfere with investments.