Buster Martin raised £200,000 for the Rhys Daniel Trust
The Guinness Book of Records has refused to accept a London Marathon runner's claim he is the race's oldest runner, at 101 years of age.
Buster Martin, who was born in France and raised in a British orphanage, has a certificate of naturalisation but no birth certificate.
Guinness World Records said until it gets sufficient evidence from Mr Martin proving his age they cannot verify it.
Mr Martin said: "I'm 101. And that I'll stick to as I know how old I am."
A spokeswoman for Guinness World Records said: "Buster Martin has applied to us but he has not been able to present sufficient evidence for us to verify his age for the record.
"Until he does we will not be able to confirm that he is the oldest man to run the London Marathon."
Mr Martin still works as a part-time valet at a plumbing company in central London.
A spokeswoman for Pimlico Plumbers said Mr Martin completed the marathon in just under 10 hours and had raised more than £20,000 for the Rhys Daniels Trust.
The charity provides accommodation for families close to specialist hospitals while children are undergoing life-saving treatment.
She said: "Charlie Mullins (the managing director of Pimlico Plumbers) has never had any reason to doubt him. This was never about a mention in Guinness World Records, this was about raising money for the Rhys Daniels Trust.
"Quite frankly, whether he is 94 years old or 100, what he has done is just amazing."
Mr Mullins said: "He is adamant that is his age. That is what he told us and we did all the standard checks and they all came back to us that that is how old he is.
"He has got British citizenship from the Home Office that says how old he is."
Guinness World Records lists the oldest man to complete a marathon as the Greek runner Dimitrion Yordanidis, aged 98, in Athens in 1976. He finished in seven hours 33 minutes.
The oldest woman to complete a marathon listed by Guinness World Records is said to be Jenny Wood-Allen who completed the London Marathon at the age of 90 in 2002.
She finished in 11 hours and 34 minutes.