Improvements to the pension system have been ordered after a war veteran lived in poverty for 22 years because he was not told what money he was entitled to.
Pensions secretary Iain Duncan Smith has called for a tightening of procedures after learning of the case of Chelsea Pensioner Tom Isted, who died last year aged 86.
Mr Isted, who was originally from Horsley Road in Chingford and served during the Suez Crisis, received an army pension which covered his rent at the Royal Hospital in Chelsea.
But it wasn't until after his death that his family discovered he had spent the last 22 years of his life earning less than £50 a month doing small jobs at the hospital because he didn't realise he was also entitled to a state pension.
Mr Isted's son David, who still lives at the family home in Chingford, says the government should have done more ensure his father was provided for.
The Merchant Navy captain added: "I’m at a complete loss. He served in Palestine, battled in Adan and was at the heart of the Suez conflict for his majesty’s government, but he got nothing in return.
"He was a proud man and a gentleman so he would never discuss his finances. If only we’d known.
"He could have travelled more, he could have had a much better quality of life, all for the sake of the government making a phone call. It’s bureaucratic nonsense. I think it’s disgusting."
When Mr Isted made inquiries about why his father had been left living in poverty, he was initially told the pensioner had rejected a state pension in 2001.
But it was later admitted that this was not true and he had simply not claimed it.
When Mr Isted contacted Iain Duncan Smith looking for answers, the Chingford MP, himself an ex-serviceman, vowed to do all he could to ensure others do not suffer in the same way.
In a letter he said: "I have considered whether the policy around claiming the state pension is correct, in light of your father’s experience.
"I have asked the Pension, Disability and Carers Service to look again at their procedures and advise me on what adjustments can be made, so that this situation does not arise again."
And Mr Isted hopes this means other vulnerable ex-servicemen will be protected.
"I feel terrible about what happened to him but so many army veterans come out of it not knowing what their entitlement actually is.
"The government should do the right thing – this could affect thousands of people," he said.