Lord Rothermere attended dozens of meetings with senior politicians, including David Cameron and Culture Secretary Jeremy Hunt.
The chairman of the Daily Mail and General Trust, which owns the Daily Mail and Mail on Sunday, described a visit to Chequers in July 2010 with the Prime Minister and his wife Samantha.
The cross-bench peer and Lady Rothermere also spent a weekend with George Osborne and his wife in November 2009, as well as socialising with Liberal Democrat leader Nick Clegg, Gordon Brown and Tony Blair.
But giving evidence to the Leveson inquiry, Lord Rothermere insisted there had been nothing improper about the contacts.
And he stressed that, despite people's worries about the influence and behaviour of the press, the Daily Mail had "acted ethically".
"I can see why people have concern for the press. After all it does appear to have quite a lot of power and certain elements of our industry have not necessarily acted in the right way, apparently," Lord Rothermere said.
"I feel pretty confident that our newspaper has acted ethically and I am willing to stand up for us."
He accepted that the Mail had to be more protective of its reputation in the wake of the furore about media standards.
"As a leading newspaper we have to take that on board," the peer said. "However, ultimately the commercial reputation we have is with our readers and advertisers.
"They continue to read our newspapers and advertise with our newspapers."
The inquiry saw in 2002 and 2003, he had a number of meetings, including lunches and dinners, with politicians including Brown, Blair and Clegg.
But he said in social meetings, politicians rarely discussed "special interests" with him.
"In a full meeting, for example where you go to and there's public servants there then there's an agenda and you can talk about the issues that you want to discuss," he told the inquiry.
But he said in personal engagements, politicians would talk about "what they are trying to do with the country and their vision", as well as sometimes complaining about papers not supporting them.
"But they don't talk about the commercial interests of our newspapers, nor do I encourage them to," he said.
Lord Rothermere said he had sent just two text messages to ministers - one to Mr Clegg and one to Mr Cameron - after the public debate before the last general election, in which he said he wrote: "Congratulations on a job well done".
"That's the only two text messages I can recall ever sending them," he told the inquiry.
He said meetings with politicians were not an effort to secure favours: "There's no reason for us to have done that. There's no favours that we sought anyway."
He told the inquiry that during the weekend at Chequers in July 2010, with Mr and Mrs Cameron; Mr Hunt and his wife Lucia, and Education Secretary Michael Gove and his wife, he did not discuss the Murdoch empire's BSkyB bid.
"The only conversation I had with any minister about media issues was when Jeremy Hunt arrived, we talked a bit about local TV.
"Jeremy was very passionate about his ideas for local TV and wanted us to be a core participant of that and he talked to me briefly about that.
"But it was in passing, it was perhaps less than a few minutes conversation, and that was the only thing that we discussed."
He said he was "absolutely positive" they had not discussed the BSkyB bid.
Again, on a meeting on August 25, 2010 at the Department for Culture, Media and Sport with Mr Hunt and his deputy Ed Vaizey, he said the bid was not discussed.
Pressed by counsel for the inquiry Robert Jay QC whether it had definitely not been mentioned on either occasion, he added: "At Chequers it was a friendly weekend, we were getting on, I didn't want to bring up business."
He said "it's sort of rude to do that" when you are invited by someone else, "even if it is the Prime Minister, on a friendly basis".
He added: "With Jeremy Hunt and Ed Vaizey, we had a strict agenda and I didn't feel it was appropriate to bring it up either."
When asked about the Mail’s coverage of Madeleine McCann in 2008, Rothermere said some of it was “regrettable”.
"As a parent you would have to be inhuman not to feel deeply" about Madeleine going missing,” he said.
“Firstly, it was obviously a very big story because of the nature of it. The McCanns encouraged publicity for very good reasons. And then there was, I believe, the problems of the jurisdiction in Portugal creating briefings. I think our journalists were unfamiliar with the way the Portuguese police operate.”
He added: “A number of allegations were made which we regret… and immediately rectified it and made a donation. It's a regrettable occurrence but it is the nature sometimes of journalism to do that.”
Rothermere was also questioned on the Mail’s alleged dispute with the Express and its proprietor Richard Desmond, which was highlighted in Jonathan Powell’s book The New Machiavelli.
When Desmond’s Northern and Shell bought Express newspapers in 2001, the Mail wrote unflattering articles about Desmond’s suitability to own a national newspaper due to his portfolio of pornography titles.
The Express responded by writing similarly unflattering articles about Rothermere’s family, specifically his illegitimate son.
He said: "He seemed to think the fact I have an illegitimate son is of some concern. I am very proud of my son. I don't make a secret of it – the idea I am offended by it is slightly offensive."
The former News of the World editor, Andy Coulson, is due to give evidence on Thursday afternoon.