The B.C. government filed its application for intervener status in court challenges against the Trans Mountain pipeline expansion on Tuesday.

The NDP government announced earlier this month that it would be joining the legal fight against Ottawa's approval of the $7.4-billion project.

Nineteen separate lawsuits from First Nations and environmental groups will be heard as one case in federal court.

The move by the province is part of its pledge to do everything it can to kill the controversial project to twin the existing pipeline that runs from Alberta to the West Coast.

The B.C. government has hired lawyer Thomas Berger, a former B.C. Supreme Court justice, to provide advice to the government on the legal challenges.

Attorney General David Eby says the majority of the pipeline is in B.C. and the government should be able to represent the interests of people in the province — notably because the Alberta government has already been granted intervener status

Alberta Premier Rachel Notley says they'll argue in favour of the project, citing public interest and economic benefits.

Appeal hearings for the federal court challenges are set for November,