A Canadian company said Tuesday it plans to start construction of the disputed Keystone XL oil sands pipeline through the U.S. Midwest in April, after lining up customers and money for the project that is bitterly opposed by environmentalists and some American Indian tribes. Construction is set to begin at the pipeline’s border crossing in Montana, said TC Energy spokesman Terry Cunha. That would be a milestone for a project first proposed in 2008. The company said it lined up $1.1 billion in financing from the Canadian provincial government of Alberta to cover construction through 2020 and agreements for the...