Manitoba's new premier was sworn into office on Tuesday while her opponent challenged her leadership victory in court.

"It's disappointing," Heather Stefanson said. "But I'm not going to let this get (us) off our game, our focus."

In her first speech as premier, Stefanson promised to strengthen health care and the economy. The government is also committed to listening to and learning from Indigenous people to advance reconciliation, she said.

"I will always listen to you, the people of Manitoba," she said.

Stefanson added that she expects the legislature to return later this month with a throne speech. She did not say whether there would be significant changes in cabinet, but suggested it's not unusual for roles to shift under new leadership.

Stefanson, 51, became the first woman to become premier of the province after Progressive Conservative party members chose her as their new leader on the weekend.

"While I may be the first woman to hold this office, I take this oath confident in the knowledge that I will not be the last," she said.

She is also the only female premier in the 10 provinces.

Shelly Glover, who narrowly lost to Stefanson when the leadership ballots were counted Saturday, is challenging the result. She claimed that the wrong person has been sworn in.

Progressive Conservative Leader Heather Stefanson sworn in as Manitoba's new premier. #MBPoli

"I feel I am the first female Métis premier of Manitoba," Glover said.

In court documents filed Tuesday, Glover argued that Stefanson's win is invalid and that the premier's office remains vacant. She said in an affidavit that she was given different numbers of how many votes would be counted than what was eventually provided.

Stefanson won by 363 votes.

The Progressive Conservative party said the leadership vote was run independently and ballot counting was overseen by party auditors as well as a scrutineer from each campaign.

"We hope that after our election committee talks to Ms. Glover and her advisers and responds to her concerns that they will see that the process and the results were handled appropriately, accurately and without favour," the party said in a statement.

Glover, a former Conservative member of Parliament, had complained throughout the leadership race that many party members didn't receive their ballots in time.

Through her lawyer, Glover wrote to Manitoba's lieutenant-governor Monday asking for the swearing-in to be delayed so she could contest the outcome of the leadership vote in court.

The head of the Tory leadership committee said on the weekend that every effort was made to allow people to vote and no one was deliberately denied a ballot.

Stefanson was first elected as a legislature member in 2000 and has held the Tuxedo constituency in Winnipeg ever since.

She has promised a different tone than her predecessor, Brian Pallister, who stepped down in September after dropping significantly in opinion polls following controversial remarks about the history of Indigenous people. He was also criticized for the his government's response to the COVID-19 pandemic.

Stefanson didn't escape criticism during the province's worst wave of the pandemic. She was health minister last spring when dozens of patients in intensive care had to be flown to other provinces because of a shortage of beds.

Opposition NDP Leader Wab Kinew congratulated Stefanson on becoming Manitoba's first woman premier, but urged her to reverse her predecessor's decisions around health care.

Stefanson also served as deputy premier, justice minister and minister of families since the Progressive Conservatives won a large majority in 2016.

She said she understands that it will be a significant challenge to regain the trust of Manitobans, but it's one that she's ready to face as premier.

"We are starting on the ground running right away."

This report by The Canadian Press was first published Nov. 2, 2021

— With files from Brittany Hobson

Keep reading