The president of one of the largest Native American tribes in the U.S. announced Tuesday he has removed responsibilities from his vice president, saying she no longer represents his administration and should consider resigning from the highest office within the Navajo Nation to ever be held by a woman.

Navajo Nation President Buu Nygren made the announcement in a news conference that was broadcast on social media. The tribe has been mired by political upheaval since April, when Navajo Vice President Richelle Montoya publicly outlined allegations of intimidation and sexual harassment within the administration.

An independent investigation of Montoya's claims was initiated while other opponents of Nygren began collecting signatures from voters across the reservation — which spans parts of Arizona, New Mexico and Utah — as part of an effort to recall the president.

Nygren took aim at the recall effort and outlined his reasons for terminating Montoya's authority during the news conference. He accused his detractors of failing to focus on issues affecting Navajo families, such as housing and employment needs along with access to drinking water, electricity and other basic services.

“We will not be hindered or delayed by self-seeking power-chasers who do not want to be held accountable for their actions and care more for their own promotion than they do for the betterment of the Navajo people,” Nygren said.

In a memo sent to Montoya on Tuesday, Nygren said her decision to “do nothing productive must come with consequences.”

Montoya was preparing a response to the president's announcement Tuesday afternoon. In July, she sent her own six-page memo to Nygren, accusing him of deviating from their collective vision and “betraying the trust of the people who voted for us as equals.” She said her ideas and recommendations were no longer sought after the inauguration and that she was removed from critical communications and planning.

She also said in the memo that the president's actions had exacerbated the rift but that she continued to work on behalf of the Navajo people despite the lack of support.

An ardent supporter of Nygren during his campaign in 2022, Montoya took to social media in April and reported that she was intimidated and sexually harassed during an August 2023 meeting in the president's office.

Navajo Nation Attorney General Ethel Branch confirmed last week that the investigation into Montoya's claims was ongoing. Branch acknowledged frustration that the process has yet to be completed but noted that numerous interviews were required along with the review of what she described as significant documentation.

Montoya made history in 2023 when she took office along with Nygren. At the time, she paid tribute to women on the Navajo Nation Council and in the matriarchal society while encouraging tribal members to speak the Navajo language and always think seven generations ahead.

“For the next four years, I will give you my very best,” she told a crowd as the pair was sworn in during a gathering in Fort Defiance, Arizona.

Nygren has accused Montoya of failing to make progress on the priorities he had set out for her, saying she has refused requests to submit daily schedules and reports and has instead made travel requests that don't align with the administration's priorities.

“Everyone in my administration is held accountable, including myself. The vice president is no exception,” he said.

Nygren said Montoya's decision in September to sign the recall petition targeting him was “her announcement to the Navajo people of her formal break from this administration.”

The organizers of the recall effort include Debbie Nez-Manuel, who was dismissed earlier this year from her role as director of the tribe's human resources department. Nez-Manuel disputed Nygren's accusations that she had bullied employees and told The Associated Press on Tuesday that she was following the law and that employee complaints followed personnel actions.

A well-known Democratic Party organizer, Nez-Manuel said Nygren has fallen short of voters' expectations and suggested that he has not given the vice president the tools needed to succeed. She said many of those who have signed the recall petition have raised concerns about elder Navajos not trusting the younger generation to serve as leaders.

“He needs to resign, and that will balance out what’s happening,” Nez-Manuel said.

Nygren said his administration has been successful in meeting the needs of Navajos, pointing to the connection of more homes to water and electricity services and the recent negotiation of historic water rights settlements.