Thousands of well-wishers are expected to arrive in Windsor Castle to greet Britain's Queen Elizabeth II as she is celebrating her 80th birthday with the royal family on Friday.

Public celebrations are scheduled to start in the morning with a 21-gun salute in the parkland close to Windsor Castle.

The monarch and the Duke of Edinburgh are expected to emerge from Windsor Castle shortly after midday as a military band plays "Happy Birthday" and members of youth groups presenting cards and flowers. The Royal couple will then meet the public during a walkabout in the center of Windsor Town.

Buckingham Palace said the Queen had received 20,000 cards and 17,000 e-mails from home and abroad.

"I would like to thank the many thousands of people from this country and overseas who have sent me cards and messages on my 80th birthday. I have been very touched by what you have written and would like to express my gratitude to you all," the Queen was quoted by the British Broadcasting Corporation (BBC) as saying.

Prince Charles will deliver a "short and affectionate" televised birthday tribute to his mother, Europe's longest-serving living monarch, later in the afternoon, before hosting a private dinner at Kew Palace in southwest London.

The Queen has revealed she wants "a nice sunshiny day" on her 80th birthday.

Celebrations are also taking place across Commonwealth countries.

Five hundred people of different ages formed a giant human 80 on the front lawn of Government House in Wellington, New Zealand.

The Queen has two birthdays. The official birthday will be celebrated on July 17 with the national Trooping the Colour parade.

At 80, the Queen has become one of some 330,000 octogenarians in Britain.

The Independent Television conducted a survey earlier this week among 1,500 people, which showed that 68 percent of those polled want a Monarch for the country and 57 percent want Queen Elizabeth to reign until she dies.

Nonetheless, calls for Britain to become a republic is also audible, with 13 percent supporters.

The Guardian newspaper published an article on Friday, saying "Let's wish the Queen a very happy birthday. And when she goes, let's bury this ludicrous institution".

Source: Xinhua