VANCOUVER -- The governor of Washington says his state is "allied" with British Columbia in questioning whether the Trans Mountain pipeline should be expanded.

The project poses a threat to waters off the West Coast, which Washington residents view as a treasure, and the state is looking at marine safety laws that would help mitigate the impact of a tanker spill, Gov. Jay Inslee said Friday at a meeting with B.C. Premier John Horgan and officials from Oregon and California.

"We are hopeful that the premier's efforts to allow the voices of his citizens to be listened to will be successful, because it is very much in common with our citizens," Inslee said, adding that residents in his state recently rejected proposals for both coal and oil ports.

Inslee commended British Columbia for leadership on climate protection. But he said Trans Mountain may be a federal policy that "shoots Canada in the foot" and reverses some of the work the province has done.

Alberta and B.C. have been locked in a battle over the future of Kinder Morgan's $7.4-billion plan to triple the capacity of the Trans Mountain pipeline, which runs from Edmonton to Burnaby, B.C.

Federal Environment Minister Catherine McKenna acknowledged Friday there are differences over the pipeline, but she said it was approved by Ottawa after extensive reviews and it will be built.

"We did that review by increasing engagement with communities, by meaningful consultation with Indigenous Peoples, by looking at the science and the evidence and also looking at the project in the context of our climate plan, and we approved that project," she said in Victoria.

"The project was also approved by the previous B.C. government and we think the project should go ahead."

B.C. is asking the courts to determine if it has jurisdiction to limit how much diluted bitumen can flow through pipelines in the province.

The members of the Pacific Coast Collaborative met in Vancouver on Friday to mark its 10th anniversary and agreed to add drug overdoses and trade to the list of issues considered vital to the four jurisdictions.

The forum was created in 2008 to encourage joint action on matters like climate change and the environment but the group also wants to confront what Inslee calls the "scourge of substance-use disorders."

A news release from the premier's office says they are also committed to ending the stigma and discrimination associated with addiction and substance-use disorders.

Later on Friday, Horgan announced B.C. will contribute $300,000 towards a study with Washington state on the potential for a high-speed rail line connecting Vancouver, Seattle, Portland and other cities beyond. Washington has approved funding of up to US$1.2 million towards the new study.

B.C. says the service could cut travel times between Vancouver and Seattle to about 60 minutes from three hours.

Collaboration throughout the Pacific region is particularly important in the current political climate, said Matt Rodriquez, California's secretary of environmental protection.

"To be candid, for those of us in the United States, there's an absence of leadership in the federal government right now and so it's incumbent on us to work together and step up and show what we can do between our various governments," he said.

Inslee said that collaboration is evident in the group's approach to climate change.

"On the West Coast, we know that climate change is not a hoax," he said. "It doesn't matter what foolishness comes out of the White House. Leaders on the West Coast are united in understanding science in the commitment to clean waters and clean air."

The group is a physical representation of governments working together across borders on critical issues, Horgan said.

"I believe we're demonstrating to North America the commonalities that we have despite artificial boundaries," he said.

"The 49th parallel exists on maps and on globes, but we've demonstrated today that working together, the people who populate this spectacular region have a common purpose. And that is to ensure that our environment is protected so our economy can flourish."

Horgan said his U.S. counterparts understand the urgent need to protect a shared environment and to slow climate change across a region that is home to 55 million people and represents the world's fifth-largest economy.