PINE RIDGE, S.D. (AP) – A Native American tribe has told South Dakota’s Republican Gov. Kristi Noem she’s not welcome on one of largest reservations in the country after she led efforts to pass a state law targeting demonstrations such as those in neighboring North Dakota that plagued the Dakota Access oil pipeline.

“I am hereby notifying you that you are not welcome to visit our homelands,” Oglala Sioux President Julian Bear Runner said in a letter to Noem following a 17-0 Tribal Council vote on Wednesday approving the action. He told Noem that if she ignores the directive “we will have no choice but to banish you” from the the Pine Ridge reservation.

Banishment is a formal tribal process in which a person can be barred permanently from the reservation. Violations can result in fines or even jail time, but Bear Runner spokesman Chase Iron Eyes said the tribe’s goal is to show its unhappiness with Noem and that “no one wants to go through the steps to actually banish a sitting governor.”

“The notion of banishment has not been considered by the Tribal Council,” he said. “The president just wanted to make the letter as clear as possible as to what the options might be.”

Noem traveled to the reservation in late March after she activated National Guard soldiers to help with the tribe’s flood response — a trip Iron Eyes said was welcomed by the tribe. However, he said she has made at least one and possibly two trips since without notifying the tribal government, presumably to speak with reservation residents about the laws.

A statement issued by Noem’s spokeswoman Thursday said “It’s unfortunate that the governor was welcomed by Oglala Sioux’s leadership when resources were needed during the storms, but communication has been cut off when she has tried to directly interact with members of the Pine Ridge community.

“The governor will continue working to engage with tribal members, stay in contact with tribal leadership, and maintain her efforts to build relationships with the tribes,” spokeswoman Kristin Wileman said.

Legislation that Noem and GOP leaders pushed through in a matter of days in March allows officials to pursue money from demonstrators who engage in “riot boosting,” or encouraging violence during a riot.

Activists and American Indian tribes plan on-the-ground protests against the Keystone XL pipeline if it’s built, similar to protests against the Dakota Access pipeline in North Dakota in 2016 and 2017. Those demonstrations , in which American Indians played a key role, resulted in 761 arrests over six months and cost the state $38 million.

Noem has said the South Dakota law is meant to address problems caused by “out-of-state rioters funded by out-of-state interests.” The American Civil Liberties Union and tribes contend the law stifles free speech, and the ACLU is suing Noem, Attorney General Jason Ravnsborg and a county sheriff in federal court on behalf of activists.

The Oglala Sioux is not a party to the suit but says in a statement, “the Governor has been asked not to set foot upon a swath of land the size of Delaware and Rhode Island combined.”

TransCanada Corp.’s planned Keystone XL pipeline would move Canadian crude through Montana and South Dakota to Nebraska, where it would connect with lines to Gulf Coast refineries. The $8 billion project has the backing of President Donald Trump but is being fought in the courts by opponents.