Fraudsters targeted the 75 year-old widower just weeks before Christmas by purporting to be from her bank, NatWest. The sophisticated scam, known as 'vishing', involves a fraudster making a phone call posing as a bank representative and persuading victims to reveal financial information or authorise payments online.
Mr Davies described such frauds as 'devastatingly cruel' and said banks owe a much greater 'duty of care' to customers.
He has taken up the woman's case after being contacted by members of her family. Despite an ongoing investigation, NatWest has so far not admitted liability for the loss of the money.
Mr Davies said, "This is a very serious case which has left an elderly widow penniless.
"The victim received a phone call claiming to be from her bank's security team informing her that an attempt had been made to use her card at Tesco and Asda.
"Once she had confirmed it was not her, she was advised to cancel her cards and transfer her savings to a holding account.
"This was to be opened up by the following morning together with the issue of new cards, which unfortunately she agreed to."
Upon checking the next morning and discovering that her life-savings had disappeared, the legitimate fraud unit at NatWest was notified.
Mr Davies said the fraudsters have 'no moral principles' and suspected the elderly are targeted because they are trusting.
He said, "Sadly, these vishing scams are becoming all too common and I personally believe banks could be doing much more to protect customers.
"I strongly advise the public to be on their guard. People should never give out account details over the phone but instead go to the local branch of their bank.
"Scammers have also found a way of staying on the line after victims have hung up the initial call, so if they are asked to call back a different number they end up speaking to the same person again.
"I have taken up my constituent's case with NatWest and hope there will be a positive outcome shortly."