Former Post Office head of partnerships Angela van den Bogerd has admitted there was “rumblings” of errors with the Horizon system as far back as 2004.

Ms Van den Bogerd was asked by Jason Beer KC during the Post Office Horizon IT Inquiry if concerns raised in 2004 could be classed as an “early rumbling”. She replied: “Yes.”

The enquiry was shown an email sent to her in 2004 from a colleague in relation to a sub-postmaster called Stephen Morgan who had a shortfall of more than £1,400.

It read: “I…have one of my team onto this – Richard Benton.

“I have asked Richard to put together a checklist of obvious things that could have caused this discrep [discrepancy] in the Branch. If we can discount those it gives us a greater level of confidence that it really is Postmaster error.”

Ms Van den Bogerd also told the enquiry she did the “best I could” and never “knowingly” did anything wrong.

She said: “I didn’t knowingly do anything wrong, and I would never knowingly do anything wrong.”

Ms van den Bogerd also insisted that “I was certainly not trying to cover up or suppress”, issues relating to remote access in the Horizon software.

Elsewhere, Labour has promised to unlock the “trapped potential of our railways” by bringing them under national ownership if it enters No 10.

In a major speech in London on Thursday, Louise Haigh, the shadow Transport Secretary, said the party would “sweep away the broken model and bring private operators into public ownership”.

Labour plans to unite the complex structure of dozens of rail lines into a unified system, called Great British Railways.

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