Nicola Byrne, the national data guardian for England, has criticised the National Health Service England for failing to disclose that employees of Palantir would be given “unlimited” access to identifiable patient information.

The incident demonstrated “how quickly confidence erodes”, and was a breach of the “no surprises” principle set out in the Caldicott Principles that govern the use of NHS data, Byrne said.

“The intensity of interest and strength of public feeling on this issue appear to reflect not only how deeply many people care about the use of their data, and its confidentiality, but also continuing concern amongst some about Palantir’s role in the NHS,” said Byrne in a statement.

“This topic has always been to some extent political. As such, people have a range of views . . . This means that accuracy and transparency must remain central priorities for the NHS FDP (Federated Data Platform) programme.”

Palantir, a company with right-wing political ties in the United States, and whose executives have expressed extreme ideological views, is building the FDP project under a £330 million contract to consolidate NHS data sources.

In May, the Financial Times reported that NHS England had created an administrator role for a small number of Palantir staff for a part of the FDP in which data is stored before being anonymised.

In an internal briefing note, the body said this “permits unlimited access to non-NHSE staff”.

NHSE later acknowledged that the original data protection impact assessment submitted for the FDP failed to disclose that identifiable patient data would be shared directly with Palantir employees, Byrne said.

NHSE said it was “committed” to being transparent about the use of patient data, and would implement Byrne’s recommendations.

The body earlier said the project had resulted in a 15 percent fall in long-stay discharge delays for hospitals using the FDP, but an analysis by the Health Foundation found that the project had made “no noticeable improvement” to patient discharge performance.