The New York Times has abruptly replaced its executive editor, Jill Abramson, and named managing editor Dean Baquet to replace her at the top editorial post.

Abramson's departure was announced on Wednesday by the newspaper’s publisher and chairman of its parent company, Arthur Sulzberger, and the paper's own report said: "The reasons for the switch were not immediately clear."

Abramson, the first woman to hold the newspaper's highest editorial position, and Baquet had both been in their current positions since September 2011.

“It is an honour to be asked to lead the only newsroom in the country that is actually better than it was a generation ago, one that approaches the world with wonder and ambition every day,'' Baquet said in a statement released by the newspaper.

Baquet, 57, received a Pulitzer Prize for investigative reporting in 1988, and will be the first African-American in the top editorial position. Sulzberger called Baquet the best qualified journalist to take on the job in the Times' newsroom.

Sulzberger told stunned staff members on Wednesday the appointment of Baquet "would improve some aspects of the management of the newsroom," according to his remarks obtained by Reuters news agency.

He did not elaborate on what those issues were but said they did not relate to the direction of the journalism or the paper's digital future.

"This is also not about any sort of disagreement between the newsroom and the business side over the critical principle of an independent newsroom," he said.

In its most recent quarter, the Times Co. saw overall advertising revenue rise for the first time in three years, jumping 3 percent to $158.7m.

The company's print and digital advertising rose compared with the same period a year ago.

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