The scandal over the breast cancer screening deepened today after the IT company involved hit back at suggestions that their software was to blame.

Senior sources at Hitachi Consulting said that they had created an algorithm following the exact specifications provided by health officials.

They also questioned why Public Health England (PHE) failed to act after the firm flagged up concerns in March 2017 that women were being denied scans.

Until now, PHE had defended itself by insisting that it had been informed by Hitachi that the problems were localised.

But a well-placed source at the consulting company said: “In March 2017, this was escalated to senior officials at Public Health England. They didn’t call it up.”

A separate source close to the breast screening programme told The Telegraph that any suggestion of an IT blunder was ill-founded. The source blamed the problem on the specification provided to the computer software companies by the NHS.

“The programme was doing exactly what it was supposed to,” said the source, “It was programmed to the correct specification.”

Up to 450,000 women aged 68 to 71 eligible for breast cancer screening checks were denied mammograms as a result of an error that was not spotted for almost a decade.