London - Swiss-based Sauber have parted company with principal Monisha Kaltenborn, the first woman to run a Formula One outfit, the team's owners said on Wednesday.
"Longbow Finance SA regrets to announce that, by mutual consent and due to diverging views of the future of the company, Monisha Kaltenborn will leave her positions with the Sauber Group effective immediately," they said in a statement.
"Her successor will be announced shortly," it added.
The team are due to compete this weekend at the Azerbaijan Grand Prix in Baku.
No details were given about the 'diverging views' but board chairman Pascal Picci issued a separate statement, angrily rejecting speculation that it concerned the status of the team's drivers and a desire to favour Sweden's Marcus Ericsson.
"The owners and board of Sauber Motorsport AG take strong exception to speculative and widespread media reports today that our race drivers have not been, and are not being, treated equally," he said.
"This is not only patently untrue, it would be contrary to the team’s absolute and longstanding commitment to fair competition.
"These reports, attributed to anonymous 'sources', are highly detrimental to both Marcus Ericsson and Pascal Wehrlein as well as to the management and all staff of the Sauber F1 Team."
Ericsson have yet to score a point in seven races this season but have important backers while Wehrlein, who has a long-term Mercedes contract, finished eighth in Spain in May.
Motorsport.com said the terms of Kaltenborn's departure were still being worked out.
Kaltenborn, an Indian-born Austrian citizen, took over from team founder Peter Sauber in 2012.
The sport's first woman team principal, and the second Indian-born after Force India's Vijay Mallya, Kaltenborn joined Sauber in 2000 to run the legal department and took over as chief executive in 2010.
The team fell on hard times in recent seasons, struggling to score points last year, but the financial problems eased when Longbow, a Swiss-based investment company, took over in July last year.
They recently agreed with Honda to switch to the Japanese manufacturer's engines next year instead of using year-old Ferrari ones.
Kaltenborn's departure will leave former champions Williams as the only team with a woman in charge. Claire Williams is officially the deputy principal to father and founder Frank but effectively runs the team day-to-day.