Tony Blair took aim at tabloid journalism during his appearance at Britain's media ethics inquiry Monday, both criticizing the business and admitting he wasn't willing to risk offending journalists while he was prime minister.

Blair, who called Downing Street home between 1997 and 2007, told the judge-led inquiry that interactions are inevitable between politicians and journalists.

"That has always been the case and that will always be the case," Blair told the inquiry at the Royal Courts of Justice in London, adding that "it'd be strange frankly if senior politicians and senior journalists didn't have those interactions."

He also acknowledged that, as prime minister, he made a conscious decision not to pick a fight with the media establishment.

He admitted that he made a "strategic decision to manage these people, not confront them," because to do so would mean waging a battle there was no guarantee he could win.

"If you're a political leader and you've got very powerful media groups and you fall out with one of those groups, the consequences is such that you ... are effectively blocked from getting across your message," Blair said.

"I'm being open about the fact that frankly I decided as a political leader, and this was a strategic decision, that I was going to manage that and not confront it. And we can get on to whether that was right or wrong at a later stage, but that was the decision I took," he said.

The former prime minister also unleashed a dig at Britain's popular tabloid industry.

"I think there is a genre of writing that has gone into parts of the media, but because this line between news and comment gets blurred, it stops being journalism. It's an instrument of political power or propaganda."

Set up to examine the fallout from the phone hacking scandal at Rupert Murdoch's News Corp. empire, Lord Justice Brian Leveson's inquiry is probing the extent of relationships between top politicians and senior media figures , and whether British politicians failed to do enough to curb unethical and illegal practices in the industry.

Watching the proceedings from London, CTV News correspondent Ben O'Hara-Byrne said Blair was a logical choice to kick off a week of testimony by several top politicians including current ministers such as culture secretary Jeremy Hunt, education minister Michael Gove and home secretary Theresa May.

Noting that Blair became godfather to Rupert Murdoch's daughter Grace after he left the prime minister's office, O'Hara-Byrne said the former prime minister insisted theirs was a working relationship while he was in power.

"Famously it was his courtship of (Murdoch's) Sun newspapers -- who had been hostile to the Labour party for a long time -- that was often seen as what turned the tide for 'New Labour' in the 90s when they finally won and Tony Blair became prime minister," O'Hara-Byrne told CTV's Canada AM Monday.

Blair is known to have cultivated a relationship with Murdoch even before his 1997 election victory when he flew to Australia two years earlier to speak before a gathering of Murdoch's executives.

After that appearance, the famously right-wing Murdoch issued his first-ever signals he would be willing to support Blair's left-of-centre Labour Party. And indeed, Murdoch's top-selling Sun tabloid backed Blair in each of his three successful election campaigns.

During his appearance before the inquiry last month, Murdoch told the inquiry he had never asked favours of any prime minister.

In his testimony Monday, Blair said his relationship with senior executives in the media business was professional and necessary.

"You were in a position where you were dealing with very powerful people who had a big impact on the political system," Blair explained. "If they were against you, they were absolutely all-out against you."

The former PM spoke to Murdoch three times in the lead-up to the Iraq war. Blair's decision to join then-U.S. president George W. Bush's invasion of Iraq was deeply unpopular, leading to questions whether those discussions played any part in the populist News Corp. papers all backing the war.

Blair would not apologize for his dealings with Murdoch, saying he was only one of several media executives who could have made his time in office difficult if they did not like his policies.

He also denied having any kind of deal with Murdoch, "either express or implied."

The continuing resentment over Blair's decision was made clear Monday, when a heckler burst into the inquiry shouting, "This man should be arrested for war crimes!"

After the intruder was removed, Leveson said he would investigate how the man had managed to get past security.

The goal of this week's appearances by Blair and the other senior politicians, O'Hara Byrne said, is to answer "just how much power did Mr. Murdoch have, and what kind of price did you have to pay to get him onside?"

The ongoing fallout from what began with revelations tabloid journalists had hacked into private voicemails has since revealed a pattern of bribery and blackmail rife throughout the British press.

Besides journalists, dozens of prison and military officials, executives, political operatives and police have either been fired or resigned as result.