Books of condolence have been set up at St James's Palace to allow the public to pay tribute to Princess Margaret.

Among the first to sign was Barbara Girelli-Kent who said the princess, who died on Saturday aged 71, was a "trooper".

She said: "She was symbolic of correctness, strength of character, and she had a mind of her own but great respect for Her Majesty the Queen and the royal institution."

The princess had been suffering ill-health in recent years

The Queen Mother, supported by her grandson Prince Charles, attended a private service in the chapel at Sandringham House in Norfolk.

The Duke of Edinburgh went to morning service at the nearby St Mary's Church, where Canon George Hall remembered her "love of life and all beautiful things".

The Queen is at Windsor Castle where prayers were also said.

A private service was also held at Glamis Castle in Scotland, where the princess was born.

'Free spirit'

The Queen's younger sister died peacefully in her sleep on Saturday morning after suffering a stroke and developing heart problems on Friday.

The Queen broke the news of Margaret's death to their 101-year-old mother, who has been ill at Sandringham with a persistent, chesty cold.

The flag at half-mast over Buckingham Palace

Prince Charles said Princess Margaret's death may have been a "merciful relief" from the suffering of a "vital and free spirit" after years of ill health.

He spoke movingly and informally of a "darling aunt" who entertained with her piano playing as well as her vitality, beauty and her sharp mind.

But he said the strokes she suffered over the past few years had put her through a "dreadful time".

Condolence e-mails can be sent to the princess's memorial website at www.royal.gov.uk and will be passed to her family.

And Buckingham Palace has said anyone wanting to make a donation to charity in memory of the princess should make a contribution to the NSPCC, Guide Association or the Royal Ballet.

Family's bedside vigil

Princess Margaret's children, Lord Linley and Lady Sarah Chatto, and former husband, Lord Snowdon, were at her bedside at London's private King Edward VII Hospital when she died at 0630 GMT.

Margaret tributes

Mourning period for Royal Family Palace flag at half mast Donations to NSPCC, Guides and Royal Ballet Book of condolences at St James's Palace Private funeral on Friday 15 February Service at Glamis Castle, Scotland - Margaret's birthplace