TC Energy says has not found cause of Keystone oil pipeline leak
Canada's TC Energy said on Sunday it has not yet determined the cause of the Keystone oil pipeline leak last week in the United States, while also not giving a timeline as to when the pipeline will resume operation.
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### Response: Canada's TC Energy said on Sunday it has not yet determined the cause of the Keystone oil pipeline leak last week in the United States, while also not giving a timeline as to when the pipeline will resume operation.