(CNN) The Oglala Sioux tribe in South Dakota has told the state's governor that she's no longer welcome to access the Pine Ridge Reservation, one of the largest in the country, because she signed bills that allegedly target Keystone XL pipeline protesters.

The tribe's president, Julian Bear Runner, informed Gov. Kristi Noem of the council's unanimous decision in an open letter.

"I am hereby notifying you that you are not welcome to visit our homelands, the Pine Ridge Reservation, until you rescind your support for SB 189 and SB 190 and affirm to your state and this country that First Amendment rights to free, political speech are among the truths you hold to be self-evident," he said in the letter.

He added that if Noem did not honor the directive, "we will have no choice but to banish you."

Tribal banishment is a permanent ban from the reservation, and violations are punishable by law with fines or even jail time.

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