The offer was made when a delegation of former prisoners of war delivered a letter to Number Ten asking Tony Blair for his support.

Mr Blair had earlier asked the Japanese Emperor to understand that some of the scars of war will never heal.

Mr Blair was speaking at a lunch in honour of Emperor Akihito and his Empress on the third day of a state visit dogged by demonstrations by former prisoners of war.

During lunch, Mr Blair said: "As you said at Tuesday's banquet at Buckingham Palace, many still bear the scars of war.

"For some the scars of the past go so deep they will never heal. My generation in particular has not forgotten what we owe to the generation that went before us. And we never will."

Veterans promised meeting

Veterans: Promised a meeting with Blair

Mr Blair has promised a meeting with labour camp survivors who are campaigning for compensation and an apology from Japan.

The offer was made as veterans and former prisoners of war delivered a letter to Downing Street asking Mr Blair to support the campaign.

As the letter was handed in, around 50 former prisoners of war held their latest protest outside of Downing Street.

Arthur Titherington, chairman of the Japanese Labour Camps Survivors Association, said: "The message seems to be getting across to Tony Blair that we have not been treated very well by him and I think he's feeling a bit guilty."

Evening dinner

The Emperor and his wife held a return banquet for the Queen at London's Victoria and Albert Museum on Thursday evening.

The evening began with Emperor Akihito touring the museum's Toshiba Gallery before the arrival of the royal guests for the dinner in the Raphael Gallery.

On Friday the Emperor will visit the British Red Cross Society after taking his leave from the Queen, followed by his final official engagement, a cocktail reception given by the Japan Society.

'Trip has not failed'

Kazuo Chiba: Imperial couple not humiliated

The Emperor's official spokesman, Kazuo Chiba, denied the trip had been a failure of Japanese diplomacy.

He said: "I do not think that Japanese diplomacy tried to buy the hearts and minds of the British media."

He added that the imperial couple had not been humiliated but had taken it all in their stride.

"In general when terrible things happen it is difficult to forget," said Mr Chiba.