New York Times executive editor Jill Abramson replaced

Ms Abramson was the first woman the lead the 162-year-old newspaper

In a surprise move, the New York Times newspaper has announced that it has replaced executive editor Jill Abramson - the first woman to lead the paper - with immediate effect.

Dean Baquet, 57, the paper's managing editor, has been named as the replacement.

Arthur Sulzberger Jr, chairman of the New York Times company, did not give a reason for the sudden change.

Earlier on Wednesday, the first female editor of France's Le Monde resigned.

Ms Abramson, 60, was appointed in 2011.

In a statement, she said: "I've loved my run at The Times. I got to work with the best journalists in the world doing so much stand-up journalism."

Mr Baquet, a Pulitzer Prize-winning journalist who formerly edited the Los Angeles Times, will become the first African-American to lead the paper.

Shares in the company fell more than 4.5%, ending the day at $15.06.

The New York Times recently reported net income of $1.8m, and said that both print and advertising sales had grown for the first time in several years.

Also on Wednesday, Natalie Nougayrede, editor in chief of Le Monde, quit after a power struggle with senior staff.

In a letter, published on Le Monde's website, she wrote of "personal attacks" that impeded her plan to turn around the newspaper.