MINNEAPOLIS — Tribal and environmental groups are suing the U.S. State Department for approving a plan by a Canadian pipeline company to increase the flow of crude oil from Alberta into Minnesota.

The Sierra Club, the White Earth Nation and other groups filed the federal lawsuit Tuesday seeking an injunction to halt the project. The lawsuit sayid the State Department approved Enbridge Energy’s plan to construct and operate a pipeline that crosses the U.S.-Canada border without first reviewing environmental impacts.

Enbridge won Minnesota regulatory approval in August to complete a $200 million upgrade of its 1,000-mile Alberta Clipper pipeline, boosting its flow by adding pumping stations. The line carries heavy crude from the Alberta oil sands region across the state, supplying refineries across the Midwest.

Part of the upgrade is finished, but the State Department hasn’t approved a presidential permit for Enbridge to increase cross-border oil shipments.

In July, the State Department approved Enbridge’s plan to increase its cross-border oil flows by shifting the crude into an underused pipeline — Line 3 — which already has a presidential permit to operate at higher volumes. The line also carries Canadian crude to Midwest refineries, but operates at a reduced flow for safety reasons. The 1960s-era Line 3 is corroded and has ruptured several times. Enbridge said it plans to rebuild the pipeline by 2017.

To facilitate the switch, Enbridge replaced a 17.5-mile segment of Line 3 at the border so it can operate at full capacity, and installed valves linking it to the parallel Alberta Clipper. The flows of the two lines are switched at that point, but after the crude enters the U.S., valves send it back into the newer Alberta Clipper line.

The State Department decided that the switch was legal under Line 3’s existing permit.

The Alberta Clipper runs from Hardisty, Alberta, across northeastern North Dakota and northern Minnesota to Superior, Wis. The line can transport up to 450,000 barrels of crude oil per day but Enbridge wants to increase capacity to 800,000 barrels per day. According to the lawsuit, that kind of increase requires environmental review under the National Environmental Policy Act, and the State Department must sign off on the plan.

“It’s very, very worrisome that the State Department is allowing Enbridge to refuse to go through the standard U.S. environmental review process,” said Kieran Suckling, executive director of the Center for Biological Diversity, one of the groups bringing the lawsuit.

The State Department said it doesn’t comment on litigation. Enbridge, which is not a defendant, said in a statement Wednesday that the company believes the State Department has acted lawfully.