Prince Charles visit on Thursday included private talks with French President Jacques Chirac.

It is his first trip to the French capital since he brought back his former wife's body to Britain after she and Dodi Fayed suffered fatal injuries in a car crash in a Parisian underpass.

Diana died in August 1997

A St James's Palace spokesman said: "That will be very much in his thoughts.

"Grief is a very private thing, particularly when it relates to a member of your family."

The prince began his visit by meeting with Mr Chirac at the Elysee Palace, just two days after the French leader warned that France and Britain had "differences" over the future of Iraq.

Mr Chirac also caused controversy recently with his decision to invite the Zimbabwean leader Robert Mugabe to a summit later this month, the day after an existing EU travel ban expires.

Prince Charles had lunch at the British Ambassador's residence to promote British beef, another topic which has threatened to sour Anglo-French relations.

Award

There have been no commercial exports to France since it lifted its ban on British beef in October last year, following the threat of £100,000-a-day fines if it failed to do so.

The prince sampled beef, served on cocktail sticks bearing tiny Union Jacks, from the St Merryn's abattoir in Merthyr Tydfil, Wales, which is currently the only abattoir approved to export British beef.

The prince supported British beef on his trip

He told an audience of Parisian chefs and restaurateurs that a diet of roast beef and red wine would protect the cultural heritage of both countries.

"Nothing enhances the flavour of beef more than a glass of good French red wine," he said.

"So eat British beef, drink French wine and preserve a precious, priceless heritage for our future - and for our descendants."

His gesture follows a similar lunch in Rome last year when he told Italians family farms in Britain and Italy were struggling to make a living and should be supported.

The prince is also due to meet young French students studying English at the British Council, before receiving a prestigious international environment award from the Societe de Geographie at the Sorbonne.

Charles will receive the society's Grande Medaille in recognition of his "untiring service in pursuit of harmony between man and his environment".

This includes his long-standing commitment to sustainable architecture and organic farming.