Rebekah Brooks, chief executive of Rupert Murdoch's News International, resigned on Friday amid the phone-hacking scandal engulfing the British newspaper group, she said in a message to staff.
The parent company, Murdoch's New York-based News Corp, also confirmed her resignation.
"I can confirm that she has resigned," a News Corp spokeswoman told AFP.
"I can confirm an internal release has just gone to News International employees."
In an internal message to staff, Brooks said she felt a "deep sense of responsibility" for the crisis that erupted last week and resulted in the closure of News International's News of the World tabloid.
"I have given Rupert and James Murdoch my resignation. While it has been a subject of discussion, this time my resignation has been accepted," wrote Brooks, herself a former editor of the paper.
"As chief executive of the company, I feel a deep sense of responsibility for the people we have hurt and I want to reiterate how sorry I am for what we now know to have taken place," she wrote.
"I have believed that the right and responsible action has been to lead us through the heat of the crisis. However my desire to remain on the bridge has made me a focal point of the debate.
{{/usCountry}}"I have believed that the right and responsible action has been to lead us through the heat of the crisis. However my desire to remain on the bridge has made me a focal point of the debate.
{{/usCountry}}"This is now detracting attention from all our honest endeavours to fix the problems of the past."