An impressive memorial to the Queen Mother was unveiled by the Queen today on The Mall, directly before and below the statue of her husband, King George VI.

The Queen was accompanied by her children and grandchildren, the Prince of Wales with the Duchess of Cornwall, Princess Anne, Princes William and Harry, and the Duke of York with Princesses Beatrice and Eugenie.

Prince Charles gave a dignified personal tribute to his grandmother, to whom he was particularly close.

“At long last my grandparents are reunited in this joint symbol which, in particular, reminds us of all they stood for, and meant to so many, during the darkest hours this country has ever faced.

“All of us gathered here today will, I know, miss my darling grandmother’s vitality, her interest in the lives of others, her unbounded courage and determination that allowed her — incredibly — to continue her official life to the age of nearly 102; her perceptive wisdom, her calm in the face of all adversities, her steadfast belief in the British people and, above all, her irresistible, irrepressible sense of mischievous humour. How blessed we were to have known her and her generosity of spirit.”

It was the kind of occasion that put last night’s Channel 4 documentary, The Problem Princes in perspective.

With the Prince of Wales’s 60th birthday looming tomorrow, Friday, celebrations got off to an exuberant start last night with an evening of comedy at the New Wimbledon Theatre, London.

John Cleese, of Monty Python fame was the master of ceremonies for the evening together with former Fawlty Towers co-star Andrew Sachs, Manuel to his fans. The idea was to give Prince Charles a very special occasion in the presence of a host of comic superstars.

Meanwhile, over at the BBC, an excellent documentary cum interview with the Prince was broadcast last night. It was conducted by Robert Hardman of the Daily Mail and examined every aspect of Charles’s life and charity work. The range of subjects over which Charles presides with great aplomb and expertise must be mind-blowing to anyone who doesn’t keep up.

Tonight, a dinner, with an orchestral performance, will be given by the Queen in honour of her son and heir. Yesterday, she was heard to praise his public-spirited work for charity and even referred glancingly to his future role as King, which is not something she normally mentions in public.

In these depressive times, you would expect the famously frugal Monarch to cut costs even at such a banquet. And indeed the wines selected by the Queen to enhance the Balmoral salmon and venison dishes, are notable but not lavish.

Puligny Montrachet Les Olivier Leflaive, 2006 at £40 ($60) a bottle, will refresh the palette without exciting aficionados of fine wine. The red, Chateau Leoville-Barton St Julien, 1988, around £100 ($150), will be excellent after a few glasses of the white.

The dessert wine is a nice 1996 Sauternes, and a suitably expansive note to end on.

The absence of conductor Riccardo Muti owing, apparently, to a disagreement over the length of his proposed programme and perhaps his fee, will not dampen spirits at what should be a glittering event.

The Prince of Wales and the Duchess of Cornwall are on a four-day tour of Japan to celebrate the 150th anniversary of diplomatic relations between Britain and the Asian industrial superpower.

Surprisingly — to some observers, at least — Camilla is proving a real hit with the crowds. Animated onlookers greeted her with enthusiasm at Keio University in Tokyo. It seemed a bit more than legendary Japanese politeness.

Meanwhile, the Prince was entertained by a disco-dancing robot during a visit to the Miraikan Museum of Emerging Science and Innovation. Prince Charles was given a demonstration by ASIMO (Advance Steps In Mobility), a machine that can perform a range of actions, including running and dancing.

Prince Charles and the disco-dancing Japanese robot

The robot began by loping in front of the slightly-startled Prince, waving its hands around and repeating, “Konnichi-wa,” Japanese for “Good afternoon.”

On another occasion, Charles and Camilla appeared to be mesmerised by a troupe of Kendo exponents who enthusiastically demonstrated the ancient martial art to the Royal guests.

The Prince and the Duchess also watched a performance of Kabuki, traditional Japanese theatre that features actors in elaborate makeup performing stylised drama.

But Charles would hardly make such an important visit without pressing his case for a “low-carbon world.” True to form, he warned his hosts that the world was facing a “climate crunch.”

In a message aimed at governments around the world, he stressed they must not let concerns with the global “credit crunch” distract them from the growing problem of the “climate crunch.”

By all accounts the visit is turning into a great success, as the Royal party find it easy to gain popular acceptability in another Monarchist country.

Clarence House has announced a “star-studded comedy gala to celebrate The Prince of Wales’s 60th birthday.”

I’m not sure how many parties that is now — at least three by my erratic counting.

The press release says it all:

“Comedy greats will help to celebrate The Prince of Wales’s 60th birthday this year with a special one-off comedy show in aid of His Royal Highness’s youth charity The Prince’s Trust.

“The show, called We Are Most Amused, will have a unique line-up with stars such as Rowan Atkinson, John Cleese and Robin Williams on stage together for one night only on Wednesday 12th November.

“The Prince of Wales, who is a keen fan of comedy, will attend the show with his wife The Duchess of Cornwall at the New Wimbledon Theatre.

“Their Royal Highnesses will be treated to a mix of live stand-up and comedy sketches from the world’s greatest comedians to raise money for, and awareness of, the work of The Prince’s Trust which helps to provide opportunities for disadvantaged young people in the UK.

“For the first time in over 25 years, stand-up comedy legend and Hollywood star Robin Williams will perform on a UK stage. Monty Python founder and comic genius John Cleese has promised something extra special in honour of The Prince’s birthday and after a long stint on the small and silver screens, British comedy great Rowan Atkinson will return to the live stage.

“The line-up will bring together the very best in comedy talent – from much-loved established names to fresh young acts from the stand-up circuit – a combination which will appeal to all ages and, above all, to comedy fan and guest of honour The Prince of Wales.

“With further acts to be announced, We Are Most Amused promises to be a night to remember and will be screened on ITV1 shortly after the live event.

“We Are Most Amused will take place on Wednesday 12th November 2008. Tickets will go on sale at 10.30am on Wednesday 1st October and prices range from £25 to £100. To purchase tickets either call 0870 060 6646, go online at www.newwimbledontheatre.co.uk or visit the New Wimbledon Theatre Box Office in person.”

It sounds like great fun, if you like that sort of thing.