The Trump administration has officially given the go-ahead to build the Keystone XL pipeline, TransCanada announced on Friday, as a presidential permit has been issued by the US State Department. In the wake of the news, environmental groups are readying for a fight.The pipeline was first proposed in 2008, but then-President Barack Obama officially rejected it in 2015, saying it wouldn't serve US interests. The move followed massive protests, as the project became a focal point for environmental activists. Donald Trump and members of his administration have called into question the well-established science of climate change.Canadian Prime Minister Justin Trudeau, meanwhile, has shown himself to be friendly to pipelines. Last year he approved two projects, and has come out in favour of Trump's push to get Keystone XL off the ground again, partly because of the jobs and better economic prospects it could bring to Alberta, which is hurting from low oil prices. Alberta Premier Rachel Notley, too, supports the project.Continue reading on Motherboard.