Britain's oldest man today said he could not believe it when he was told he was now the oldest in the world - but added he wouldn't bother celebrating.

Bob Weighton, who is 111, admitted he was taken aback when his grandson last night broke the news to him that he had inherited the title following the death of Chitetsu Watanabe, from Japan, at the age of 112.

But rather than cracking open a bottle of bubbly, Mr Weighton, who turns 112 next month, concluded it would not be appropriate to celebrate someone else's demise and simply vowed to carry on carrying on.

Britain's oldest man today said he could not believe it when he was told he is now the oldest in the world - but added he wouldn't bother celebrating

He said: 'My grandson Magnus told me in the car whilst we were travelling in Alton.

'I remember saying: "Oh goodness me, fancy this, little Robert Weighton. It's unbelievable."

'I was taken aback.'

Mr Weighton, who still lives on his own in a flat in Alton, Hampshire, was born on March 29 in 1908 and has lived through both World Wars, the rise and fall of the Soviet Union and the invention of the internet.

He added: 'I'm lucky to be this old.

'I never imagined being this old. To be honest I never even thought about getting old.'

Explaining his very British reluctance to celebrate his achievement, modest Mr Weighton added: 'It doesn't make a difference. It's just another day in a long life.

Bob Weighton, who is 111, admitted he was taken aback when his grandson last night broke the news to him that he had inherited the title following the death of Chitetsu Watanabe, from Japan, at the age of 112

'I'm sorry that someone has had to die for me to get this title. I'm not celebrating anything, my family and I are just taking things as they come.'

Grandson Magnus Weighton, 48, said: 'I'm much more proud of Bob and what he has achieved in his life rather than his age.'

Mr Weighton was born in Hull, East Yorkshire, and was the middle child of his three brothers and three sisters.

He had three children of his own and has 10 grandchildren and 25 great-grandchildren.

He remembers the outbreak of the First World War and as a teenager he trained in marine engineering.

Rather than cracking open a bottle of bubbly, Mr Weighton concluded it would not be appropriate to celebrate someone else's demise and simply vowed to carry on carrying on. Pictured: The world's previous oldest man, Chitetsu Watanabe, died on Tuesday

But by the time he qualified in 1925 the shipping industry was in decline and so he headed to Taiwan, where he worked as an English teacher and also met his future wife Agnes.

On the eve of World War II in 1939, Bob and his family attempted to return to the UK by boat, but after arriving in Canada they were informed the war had begun and they were stuck there.

After the attack on Pearl Harbour while Mr Weighton was living in Denver, in the US, his knowledge of the Japanese language meant he was recruited by the British Political Warfare Mission.

Mr Weighton said he was shocked to be told that he is now the oldest man in the world

Mr Weighton, pictured last year, has lived through the reign of five monarchs and seen 26 Prime Ministers come and go from 10 Downing Street

He deciphered enemy messages and also worked to disrupt the morale of the Japanese to try and help the Americans win their fight.

After the war, he was finally able to return to England with his wife and three children and spent the rest of his working life as a lecturer in marine engineering at City University in London, until his retirement, aged 65, in 1973.

He and his wife, who passed away in 1997, spent much of their retirement volunteering as marriage councillors and helping at youth groups in Alton.

Mr Weighton with his children Peter (top left), who is now dead, David (right) and Dorothy, in 2008 celebrating his 100th birthday

Mr Weighton was the middle child of his three brothers and three sisters. Pictured left to right: Mr Weighton in 1918 with his sister Margaret, brother David and sisters Bessie and Jean

Mr Weighton has lived through the reign of five monarchs and seen 26 Prime Ministers come and go from 10 Downing Street.

Remarkably, he had shared the title of Britain's oldest man with Alf Smith, of Perthshire, as the pair were born on the same day, but Mr Smith died last year.

Mr Watanabe, from Joetsu City in Japan, had been certified as a Guinness World Record holder for being the world's oldest man and it is thought Mr Weighton will now receive similar honours.

The oldest known living woman is Kane Tanaka of Japan, aged 117 years.