Bill Clinton told Tony Blair of his fears for Princes William and Harry in a phone call the day after Princess Diana died.

In the same call, Blair said her death was "like a star falling" and said he would personally miss her.

The emotional private conversation, on 1 September 1997, is disclosed in documents published by the Clinton Presidential Library.

It is one of many between the two leaders and political soulmates now released in 500 pages of transcripts, covering major international issues like Iraq, the Middle East and Northern Ireland.

But the transcripts also include deeply personal conversations, such as one when Blair was shocked at becoming a father again in 2000.

After Diana died in 1997, just months after he became prime minister, Blair famously paid tribute to her publicly by declaring: "She was the people's princess."

His former spin doctor Alastair Campbell has always claimed authorship of that phrase.

But the transcripts reveal Blair also spoke colourfully about her in private, too.

He told the then-president about the last time he had spoken to her.

"She said that were it not for the boys, she'd be off the board," he said.

Blair added: "She was not the Royal Family but she was liked by ordinary people, it gave her problems with the Royal establishment."

Then he said: "I will personally miss her, it's like a star falling. She was a star for them."

Clinton, expressing his fears for William and Harry, told the PM: "I worry a lot about those kids now."

Another personal chat came in April 2000 as Blair and wife Cherie prepared for the birth of their fourth child, Leo.

Clinton called the PM "dad" and joked that after the presidential elections he was "available for babysitting duties".

As they discussed balancing work and family life, Blair confessed: "I could do with a bit of help, I tell you.

"Cherie is in great form but just keeps getting bigger and bigger.

"I tell you, just the thought and I feel as if my life's about to begin again."

Discussions on policy issues included a telephone call in January 1999, when Clinton spoke about his concerns over Northern Ireland.

"I'm really worried," he said.

"Gerry Adams was here not long ago, and I had a firm talk with him.

"I am really getting kind of frustrated by them not doing anything."

Clinton also warned Blair about how Iraq could "become a real nightmare" for him when they discussed how to deal with Saddam Hussein.

He could have had no idea then just how big a nightmare Iraq would become for Blair.

"I think if we say to this guy, 'If you start to comply, we will lift sanctions', he will quickly re-establish the weapons of mass destruction programme, and it will become known in two years that he has.

"It may not happen while I'm in office, but it will for you.

"It could become a real nightmare for you."

Some of the conversations now sound bizarre, including an exchange about how the "only decoration" in John Prescott's office was a bowl of bananas.

The president then said: "My staff won't let me talk to you unless I have a banana at hand.

"I'm sitting here with a banana; it's a big, ugly, brownish one."

At that point, Blair replied: "Now Bill, I thought we should have a word about Kosovo."

(Sky)