Aston Bay Holdings Ltd. on Jan. 20 said BHP Billiton Group's BHP Billiton Ltd. unit intends to formally terminate an option agreement over Aston Bay's Storm copper project in Nunavut in northern Canada.

Under the agreement, which was signed in May 2016, BHP Billiton could earn a 75% interest in the project, with a provision in place to convert the deal into a joint venture agreement by spending C$40 million on exploration within nine years.

Aston Bay did not disclose the reason for the termination but noted that it remains confident in Storm's technical merits and that it will continue advancing the project.