LONDON — He’d already admitted relations were too tight between politicians and Rupert Murdoch’s media empire. But Thursday, British Prime Minister David Cameron sat under oath, on the witness stand, answering questions and listening poker-faced as embarrassing evidence of his own coziness was read out loud in court.

The grilling was the latest chapter in a judicial inquiry on media ethics that Cameron himself had initiated in light of Britain’s phone-hacking scandal.

He spent more than four hours testifying Thursday at the inquiry led by Lord Justice Sir Brian Leveson in proceedings carried live on TV.

It wasn’t a flattering experience.

“I am so rooting for you tomorrow,” Rebekah Brooks, head of Murdoch’s British newspapers, gushed in a message to Cameron before he gave a key political address in 2009. “Professionally we’re definitely in this together. Speech of your life? Yes, he Cam!”

It was a revealing, and slightly cringe-making, look at how close Cameron had become with one of the country’s most influential media executives. Brooks was forced to resign from her News International post in disgrace because of the hacking scandal.

She has been arrested, and is free on bail, on suspicion of obstructing justice in the police investigation of the phone hacking at News of the World, the tabloid she edited before taking the News International job.

Murdoch shut down the tabloid in July after revelations that staff members had tapped into the voice mail of a kidnapped teenager who was later found slain.

When he was leader of the opposition, Cameron flew to a Greek island to woo a vacationing Murdoch. But Cameron denied there was ever an explicit or implicit deal in which his Conservative Party extended favors to Murdoch’s giant News Corp. in return for its editorial support.

“The idea of overt deals is nonsense,” Cameron testified Thursday. “I also don’t believe in this theory that there was sort of a nod and a wink and some sort of covert agreement.”

More specifically, Cameron insisted there was no special treatment by his government of Murdoch’s multibillion-dollar bid to take over British broadcaster BSkyB, one of the media titan’s most cherished goals until he abandoned it last year in the aftermath of the hacking scandal.

Some of the sharpest questioning centered on the government’s handling of the vetting process to make sure the bid did not violate antimonopoly regulations.

Cameron defended his decision to appoint his culture minister, Jeremy Hunt, to oversee official scrutiny of Murdoch’s bid for BSkyB. Hunt has come under heavy fire from the opposition Labour Party for allegedly being biased in favor of News Corp.

Cameron said Hunt handled the process fairly.

He also said that there was nothing improper in his own relationship with Murdoch or that any quid pro quo was involved.

He also defended his ill-fated decision to make disgraced News of the World editor his communications director, even though the news executive had already been tarnished in the phone-hacking scandal.

Cameron said he chose Coulson for the key communications post because he wanted a tough man to implement his media strategy in a demanding, 24/7 news environment.

“I had met him when he was editor of News of the World, and I felt he was a very effective individual,” Cameron said of Coulson.

Cameron said he had received assurances that Coulson was not personally involved in the phone-hacking scandal, assurances that proved hollow when Coulson was forced to resign from his senior government post last year.

Material from The Associated Press is included in this report.