Martin Lewis has issued an urgent warning after scammers sent fake emails pretending to be from the Money Saving Expert team.
Martin has warned people not to be taken in by the scam and not to follow any advice they get from fraudsters.
The Financial Conduct Authority has also warned people about a "clone firm" posing as Martin's trusted website - reports Chronicle Live.
The FCA said the scammers are understood to be offering savings accounts with high-interest rates using the emails moneysavingexpert@consultant.com and Martinlewis@publicist.com.
The addresses have no connection with the real MoneySavingExpert.com or Martin Lewis.
Martin slammed the government on social media for failing to protect people from this type of fraud.
Posting a link to the FCA's warning on Twitter, he said: "And yet the government still doesn't consider scams enough of an online harm to put in the new online harms bill.
"It's completely exasperating. Make big tech responsible for what it is paid to publish!"
The Online Harms Bill will regulate social media firms and take "decisive action to protect people online”, Culture Secretary Oliver Dowden has said.
While the Bill will give Ofcom more powers to crack down on offensive social media content, the government has ruled out giving it the power to tackle online scams.
Explaining the Martin Lewis scam warning, the FCA said: "Almost all firms and individuals carrying out financial services activities in the UK have to be authorised or registered by us.
"This firm is not authorised or registered by us but has been targeting people in the UK, claiming to be an authorised firm.
"This is what we call a 'clone firm'; and fraudsters usually use this tactic when contacting people out of the blue, so you should be especially wary if you have been cold called.
"They may use the name of the genuine firm, the 'firm reference number' (FRN) we have given the authorised firm or other details."
