Rebekah Brooks spent £250,000 buying up prostitute Divine Brown for her Hugh Grant exclusive, a court has heard.
Brooks, 45, told her defence counsel Jonathan Laidlaw QC details of the 1995 scoop.
She described securing the £100,000 deal after the British actor was caught with the prostitute.
But she said the newspaper ended up spending far more money, as they went to huge lengths to prevent rival publications getting to the sex-worker.
"There was a huge interest, and once we had found Divine Brown there was an expectation that the Mail and The Sun would not be far behind and so we asked Divine Brown if she would move from her home where she had gone back to, to a different location.
"From memory, she wanted to take quite a number of her family with her. It was quite a lot of people."
Brooks said the newspaper hired a plane to fly "very smart" Brown (pictured above) and members of her family to "the desert" – she thought Nevada – to stay in a resort to prevent other newspapers finding them.
"It all seems so silly now but actually it was really important," she said.
Asked by Laidlaw how much the whole enterprise had cost, she said it could have amounted to as much as £250,000.
"It was probably one of the biggest expenses that I had ever dealt with. It was a lot of money," she said.
At the time her weekly spending limit was supposed to be £50,000 to £60,000, she said, and she was making decisions "on the hoof" in the middle of the night because of the time difference between the UK and the US.
"At the time, obviously, if I had done the wrong thing, in the morning, particularly my decision to fly the entire family to the desert was something I had to explain to the editor and managing editor."
There was fierce competition internally between the news and features desks at the News of the World, as well as with other News International titles, the jury heard.
"It was almost like the News of the World news desk would rather… the Mirror had the story than the features desk or The Sun. There was quite lot of competition", Brooks said.
She recalled one incident where her phone wires were cut by journalists from the news desk after the features department ran a story about a judge that had pleased the newspaper's bosses.
Brooks said there "was probably a bit of old-school misogyny" shown to her, but added: "If I'd been a bloke or a woman, the competition between the two desks was ingrained into the News of the World's history. They really didn't like each other."
The trial continues.
All of the defendants deny all of the charges.
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