The RCMP have blocked access to a First Nation's territory in northern B.C., heightening tensions as government officials and hereditary chiefs of the Wet'suwet'en continue to clash over the Coastal GasLink pipeline.

The Mounties have increased their presence in the area, setting up a checkpoint and restricting access along a service road that leads to three sites where the Wet'suwet'en are maintaining a presence.

Meanwhile, the Wet'suwet'en hereditary chiefs continue to assert their own laws — saying they want Coastal GasLink and the RCMP off the territory.

"Being restricted on your own territory is against our law. We've always had free access to our entire territory," hereditary chief Na'moks said.

The pipeline by Calgary-based TC Energy is meant to move natural gas from northeastern B.C. to the coast, where a liquefied natural gas plant is scheduled for construction.

On Monday, B.C. Premier John Horgan said the project will proceed, that Coastal GasLink has all the necessary permits to build its pipeline, and that "the rule of law needs to prevail" — citing a B.C. Supreme Court decision that in December granted the company an injunction for unimpeded access to work sites.

Any relationship where you're not looking down the barrel of a gun is a better relationship.​​​​​ — Hereditary chief Na'moks

Work in the area has been temporarily suspended with the exception, under an agreement with the chiefs, of some winterizing.

On Tuesday, the company released a letter from president David Pfeiffer offering to meet Na'moks on Friday. But the chiefs have said they only want to talk government-to-government with Ottawa and the province.

Among the outstanding issues for Coastal GasLink is that the Morice Forest Service Road, which is subject to the injunction, remains impassable.

The RCMP said in a news release on Monday that the checkpoint is "to mitigate safety concerns [and] … allow emergency service access to the area."

It said the hereditary chiefs, elected government officials, journalists and people delivering supplies to the area will be allowed to travel through the checkpoint with permission from the operations commander. It said other people not listed may be allowed to move through the checkpoint, with approval.

The chiefs say access is being restricted, and that the new checkpoint came as a surprise.

Communication continues between the province and the chiefs through a separate process that started last year and isn't specific to any particular project.

Speaking to reporters on Monday, Horgan said those discussions need to continue and described the Wet'suwet'en as "leaders in issues around self government and self determination and rights and title in Canada."

A notice to clear the road from RCMP sits in a tree fell across the road block access to Gidimt'en checkpoint on Jan. 8. (Jason Franson/The Canadian Press)

The Wet'suwet'en hereditary chiefs were part of a landmark Indigenous rights and title case at the Supreme Court of Canada, along with their Gitxsan neighbours. The 1997 decision affirmed that the Wet'suwet'en never gave up title to their lands but the matter has never been fully resolved between governments.

Horgan didn't say where the Coastal GasLink project fits into ongoing discussions with the chiefs, except to say: "This is a pipeline — it's an industrial project and there's so much more at stake for the people of northern British Columbia than just this project."

That includes the 20 First Nations that have signed agreements with Coastal GasLink and stand to benefit from the project.

Premier John Horgan holds his first news conference of the year in the Press Gallery at B.C. Legislature in Victoria on Monday. (Chad Hipolito/The Canadian Press)

Na'moks said the hereditary chiefs listened to what Horgan said on Monday and saw a contradiction between his touting of the rule of law and the First Nation's leadership in the area of rights and title.

Horgan's stance "weakens" the province's relationship with the Wet'suwet'en, he said.

"Here we are trying to build a stronger relationship. We are a government, we'll remain a government, we are on our lands, we'll remain on our lands, and we will govern it as we see fit."

Wet'suwet'en hereditary chief Na'Moks addresses the United Nations special rapporteur on the rights of Indigenous Peoples at at the meeting of the UN Permanent Forum on Indigenous Issues in New York last April.

But Na'moks agreed with the premier's statement that the relationship has improved over the last year

"It is better," he said.

"This time last year we had guns pointed at us. So that relationship is better. Any relationship where you're not looking down the barrel of a gun is a better relationship."