Tony Blair and Gordon Brown may have grown "closer than was wise" to Rupert Murdoch, former Labour cabinet minister Lord Mandelson acknowledged today.
The former business secretary denied there had been any "Faustian" pact between Labour and the media baron.
But, in evidence to the Leveson Inquiry, Lord Mandelson said the amount of personal contact between the two prime ministers and Mr Murdoch led to "adverse" comment.
He suggested the same was true of current Prime Minister, David Cameron, and other Conservative leaders.
"As far as the Labour Party is concerned, I do not believe, generally speaking, that the public interest was subordinated to the party's interests in seeking good relations with News International," he said in his written evidence.
"I reject the view that, under either Mr Blair or Mr Brown, some sort of Faustian pact was forged between the government and Rupert Murdoch involving commercial concessions to him in return for support from his newspapers."
He claimed that "the contrary" was the case.
But he went on: "It is also arguably the case, however, that personal relationships between Mr Blair, Mr Brown and Rupert Murdoch became closer than was wise in view of the adverse inference drawn from the number of meetings and contacts they had.
"The same, I am sure, can be said for Mr Cameron and, no doubt, his predecessors."
Lord Mandelson said Mr Blair sought to "reassure" The Sun over issues like Europe to put to rest the "famously bad relationship" between News International and Labour in the 1980s and early 1990s.
"What we all wanted to do in the 1990s, should we ever have any hope of winning a general election again - and by that time we had lost three or four - we didn't want to make permanent enemies of News International," he told the inquiry.
"Dialogues were opened" with journalists, editors and executives, "including the proprietor", Lord Mandelson said.
He added: "I don't think that's unreasonable.
"I was hopeful, I suppose, that if we started turning things around and looked like winners, he (Murdoch) might be more attracted to supporting the Labour Party but I also think that being a man who is very interested in politics and policy, that he might have needed some reassurance from the Labour Party about how genuine the changes that we had undergone were and the changes in policies that we had made.
"If we were likely to win the election and he and the management team had thrown everything but the kitchen sink at us to stop us being elected, that he might think that was commercially not a brilliant thing to do."
He said the party "wanted his support, or didn't want the same degree of trenchant opposition that we experienced from them before".
But he added: "It did not mean that we were prepared to make concessions to his commercial interests that might enable us to curry favour and draw him over the line in supporting us".
Lord Mandelson said that as a "notorious pro-European" he was uncomfortable with the concessions made to The Sun over that issue.
He said: "I felt that the concessions we were making in that policy area, at least in rhetoric and tone, was perhaps going a tad too far."
Former culture secretary Tessa Jowell disclosed earlier that she sought an assurance from Mr Blair that he had made no deal with Mr Murdoch on media regulation when she was appointed to the job.
Ms Jowell said the then prime minister promised her in June 2001 there was "no prior agreement" with the media baron.
Her role involved responsibility for the reforms that became the Communications Act, which relaxed the rules on cross-media ownership in way that critics felt could benefit Mr Murdoch's News Corporation.
"I asked him (Mr Blair) whether any deal had been done with Rupert Murdoch on the reform of cross media ownership," she said.
"He gave me an absolute assurance, which I completely accepted, that there had been no prior agreement.
"So I had no constraint on the conclusion I might reach."
Ms Jowell said she had urged Mr Blair not to see the interested parties so that her decision-making would not be undermined by direct lobbying of Number 10.
"I wanted to make sure that the meetings I had, the proposals I developed, were not being undermined by representations being made directly to Number 10, and the Prime Minister understood the risks of that," she said.
She said that she "invited lobbying" on the reforms by a wide range of media companies and other interested parties, and said she had more than 150 meetings.
"I don't think there was more lobbying from News International than other media groups," she said.
Ms Jowell insisted there had been no "negotiation" with the company over possible media reforms and that she had not discussed with Mr Blair their impact on Labour's relationship with the Murdoch empire.