Britons have invented "ridiculous" excuses to swindle money out of the welfare system, from pretending their identity was stolen to saying an identical twin claimed the payments, officials said Sunday.

The government published a list of some of the excuses used by fraudsters targeting the welfare system as it seeks to crack down on a crime which costs the taxpayer £1.6 billion ($2.6 billion, 1.8 billion euros) a year.

One purportedly jobless person claimed: "I wasn't using the ladders to clean windows, I carried them for therapy for my bad back."

Some men said they did not even know their wife had a job, with one telling inspectors: "I wasn't aware my wife was working because her hours of work coincided with the times I spent in the garden shed."

Other excuses included: "My wallet was stolen so someone must have been using my identity, I haven't been working"; and "It wasn't me working, it was my identical twin."

Minister for welfare reform David Freud said the list proved that the system was in need of drastic change.

"Benefit fraud is no joke, and yet our investigators are routinely dealing with bare-faced cheek and ridiculous excuses for stealing money from the taxpayer," he said.

The Conservative-Liberal Democrat coalition government has vowed to overhaul the system and stamp out benefit fraud.