Presidential chief of staff Kang Hoon-sik speaks to reporters at Cheong Wa Dae in Seoul, April 29. YonhapThe presidential chief of staff is considering visiting Canada early next month in his capacity as presidential special envoy for strategic economic cooperation, sources said Thursday, possibly in connection with Ottawa's submarine procurement project.Presidential chief of staff Kang Hoon-sik is planning to attend a Korea-Canada forum on energy, security and supply chains to be held in Canada in late May or early June, according to the sources.The possible visit is likely aimed at helping Korean shipbuilders win Ottawa's submarine procurement project worth the 60 trillion won ($39.9 billion).Currently, Korea's Hanwha Ocean-HD Hyundai Heavy Industries consortium is competing with Germany's Thyssenkrupp Marine Systems for the deal, with Canada expected to announce the final bidder in late June."Our government is seeking various measures to strengthen and expand cooperation with Canada, which is rich in resources, on energy, supply chains and resources," a presidential official said, adding that no final decision had been made regarding the forum, including who will attend it.