Nearly one in 10 workers whose wages were covered by the Government have said their bosses asked them to work during furlough, which was against the rules of the scheme.

The revelation comes in a report from the National Audit Office, which praised civil servants for pushing through employment support schemes at record speed, but said that, in their haste, they might have left some doors open for fraudsters.

The auditors said that HM Revenue and Customs (HMRC) should have made sure that employees knew their employer was taking furlough cash, so they could challenge potential fraud.

Around 9.6 million people were put on furlough through the Coronavirus Jobs Retention Scheme, while another 2.6 million were helped through the Self-Employment Income Support Scheme.

The NAO said there is evidence that the “schemes provided an effective bridge during the early phases of the pandemic, allowing some people to return to work when the national lockdown eased”.

By the end of July only around five million people were furloughed, while unemployment was broadly stable at 4%.

However, the number of people on payrolls dropped by half a million between March and April, and the NAO also found that one in five people who were not furloughed still had their wages or hours cut.

The NAO said the furlough scheme was rushed through at breakneck speed at the start of the pandemic. HMRC’s IT team usually needs 18 months to deliver major projects, but the furlough scheme was up and running in four weeks.