Media tycoon Rupert Murdoch has told how he can not meet Tony Blair without seeing Gordon Brown because of the distrust between the two men.
Mr Murdoch says being summoned to tea can be 'inconvenient'
"You have to be careful to have a cup of tea with them both or they are very suspicious that you are lining up with the other one," he says.
Mr Murdoch made the comments in an interview in the New Yorker magazine.
The News Corporation boss says the prime minister made himself a "lame duck" by revealing his plans to quit.
He also casts doubt on the leadership qualities of both the chancellor and Conservative leader David Cameron.
In the interview, Mr Murdoch says he has spent more time with Mr Blair and the chancellor than he ever did with ex-Conservative prime minister Margaret Thatcher.
"She didn't go out of her way to develop a personal relationship with me," he said.
"But Tony Blair and Gordon Brown, whenever I'm in town they say, 'Can't you come over for a cup of tea?'
"When you're invited by the prime minister to have a cup of tea, you have a cup of tea.
"It's sometimes very inconvenient - if you're only there two days and you have a month's work to do."
Mr Murdoch also gives his view that Mr Blair should go sooner rather than later and expressed dismay at his decision to announce that he would not be seeking a fourth term in office.
"To say 'I am going to go in four or five years', you're a lame duck from that day on," he said.
"You've seen his authority ebb away, a little bit at a time.
"The sooner we can see a face-off between Gordon Brown and Cameron, the sooner we can see the future."
However, Mr Murdoch indicates that the Tory leader has yet to impress him.
"Look, he's charming, he's very bright, and he behaves as if he doesn't believe in anything other than trying to construct what he believes will be the right public image," he says.
And on the chancellor, he adds: "Gordon has a Calvinistic approach to life, and there is a lot to be said for it.
"The question is, is he such a micromanager that he'd want to interfere with everything in the country?
"And does he still believe that the state can run everything better than private enterprise?
"He's not an old-style Labour socialist, but how much would he let the private sector get involved in health care and education - that will be the test."
Mr Murdoch would not be drawn on which candidate he is likely to back at the next election, which is not likely to be until 2009 or 2010.
On Sunday, Deputy Prime Minister John Prescott said he did not believe there were any leadership candidates who could match up to Mr Brown.
He told BBC One's Sunday AM show he believed election contests were good for the Labour Party.
But reiterating support of the chancellor, he added: "He's a hell of a man to beat but let's wait to see if there are other candidates ....
"I don't think there are any candidates... who can match up to Gordon Brown."