Key Points:

The story started: "In the last months of her life, Diana was severely opposed to Putin's efforts to become the new dictator of the Russian Federation."

The phone on my desk rang. I answered it. "Are you alone?" said a male voice.

I inspected the room briefly. It seemed empty. "Yes," I said.

"Good," said the voice, sounding slightly hoarse as if it did not want to be overheard. "It's the Foreign Office here."

"Sore Throat!" I cried.

"Sorry?" he said.

"Never mind," I said. "Carry on."

About once a year I get mysterious calls from a source at the Foreign Office. I don't know who he is. I call him Sore Throat to myself. He doesn't know that. No wonder he sounded surprised. "I am ringing you about Princess Diana's death," he said. "Were you planning to write anything about it?"

"Princess Diana?" I said. "That's hardly Foreign Office territory, is it?"

"Everything is Foreign Office territory," he said.

"Well," I said, "there isn't really anything new to say about it."

"Oh, come!" he said. "The fact that there is nothing new to be said has never stopped a journalist rushing into print! I happen to know that every day editors ring round their columnists and commentators commanding them to think of something new to say about something!"

"I must be working for the wrong papers," I said. "I sometimes get a call asking me where my copy is. That's about it."

There was a short pause, as we both realised the conversation was drifting towards shallow waters. With an effort he steered off in a new direction.

"We are coming round to the conclusion here that there may be something in the theory that her death was not accidental and that she was murdered."

I waited.

"Were you aware that in the last few months of her life Diana had begun to take more of an interest in politics?"

"I don't think I ever took much of an interest in what she was taking an interest in," I said.

He sighed. "Well, she had. And among other things she was interested in was the emergence of the new Russia from the ashes of the Soviet Union."

"Why on earth ... ?"

"We now think she may have been very heavily critical of Vladimir Putin's tactics, and severely opposed to his efforts to become the new dictator of the Russian Federation."

"But why ... ?'

"And we all know what happens to Putin's critics and opponents, don't we?"

"Just a moment!" I said. "Are you saying what I think you're saying?"

"What do you think I am saying?"

"That Putin arranged for Princess Diana to be ... "

"Ssssh," said Sore Throat. "We at the Foreign Office would never be quite so direct ... "

In the last half minute, while we had been talking, I had turned to my computer screen and had found a website which told me the dates of Putin's career.

"When she died, Putin was not yet in power," I said.

"Not quite."

"That's enough."

"He was already Yeltsin's heir apparent."

"Are you asking me to believe that Diana would have started heavily criticising a Russian politician on the grounds that he might, once he took over, start becoming dictatorial?"

"No. I am just asking you to consider circulating the rumour that Putin might possibly have had something to do with her death. We need to pile as much pressure on Putin as possible."

"You might want to put pressure on him," I said. "I don't. If I'm spotted putting pressure on Putin, I'm going to find my oil and gas bills sky-rocketing overnight."

"So you're not going to co-operate?"

"Look," I said,"what you want is someone who is interested in murder conspiracies. Give Mohamed Al Fayed a ring."

"We thought of that already."

"And what did he say?"

"He said it sounded rather far-fetched to him."

"There's your answer," I said. "If he thinks it's far-fetched, it's far-fetched."

And there he rang off. But it makes you think, doesn't it?