Vaccine passports should not be used domestically because the NHS is “very, very incompetent” at handling data, a former cabinet minister has warned.

David Davis, who was Theresa May’s Brexit secretary, said the move towards Covid certificates, set to be formally announced by Boris Johnson at a press conference tomorrow, was a sign of the government “overcompensating” for errors earlier in the pandemic.

Davis’s opposition is a harbinger of the discontent the government is likely to face from libertarians on the Tory backbenches if the theory of a passport scheme becomes reality.

“The health service has always been very, very incompetent, bluntly, at handling private data,” Davis told Times Radio. “Every time it tries to do something that is online or involves a long-range connection