NEW YORK - Queen Elizabeth II's friends dare not ask her about her personal feelings because of the wall of privacy around her, according to a US journalist who was given access to the British monarch's entourage for a new biography.

Elizabeth the Queen by Sally Bedell Smith is already a hit on both sides of the Atlantic, as Britain prepares for the monarch's diamond jubilee, which will mark the 60th anniversary of the queen's accession.

Smith, a writer for Vanity Fair, has produced biographies of Princess Diana, John and Jacqueline Kennedy, and Bill and Hillary Clinton.

Smith was given tacit approval by Buckingham Palace for her latest project and spoke to advisers, courtiers and relatives of the woman she calls "the most public and the most private person in the world".

In the book, Smith writes of the queen's fears over the divorce between her son Prince Charles and the late Princess Diana and many other dramas during her reign.

Speaking in New York, the American author and historian said that the queen has devoted friends. But because she lives "in her own little bubble and own little world", it is "a different kind of friendship".

"She tries to be amusing and she gives them very good advice, although they are very careful about not being presumptuous and calling upon her for that," Smith said.

"She is very interested in their families and what is going on. But there is a kind of a scrim in front of her," said the writer, who is also a contributing editor for Vanity Fair and a former New York Times reporter.

"They dare not really ask her about her personal feelings and personal life. She keeps a lot of that to herself. One of her cousins told me that when she gets frustrated - there is a weed in Scotland called the sticky willy - she goes out into the fields and pulls it up."

Elizabeth ascended to the British throne on Feb 6, 1952, after the death of her father King George VI. Mass national commemorations are to be held from June 2 to 5 across Britain.

The biography reveals the queen's fears after the 1996 divorce of Prince Charles and Princess Diana.

Lord Carey, the former archbishop of Canterbury, said in the book that Elizabeth was worried that her eldest son would give up his place in the line of succession for Camilla, just as King Edward VIII gave up the throne in 1936 to marry his mistress, Wallis Simpson.

The book said there were "strains" in the queen's own marriage to Prince Philip after she refused to take his family name, Mountbatten, after their 1947 wedding and Elizabeth's accession to the throne. Her family and the government had insisted on keeping the Windsor name.

But Smith wrote that Prince Philip has been a devoted husband and disputes reports that he has had multiple affairs. "What struck me was how much they are in sync," she said at the reception.

The monarch, who has never given a media interview in her six decades on the throne, cannot express political views but is portrayed as a traditional conservative, unimpressed by the New Labour moderate socialist philosophy of Tony Blair when he was prime minister.

Elizabeth's softer side was shown in her attendance at the 80th birthday party of former prime minister Margaret Thatcher, who had been weakened by several strokes.

Agence France-Presse