Three of the four sitting members of the US Privacy and Civil Liberties Oversight Board (PCLOB) have reportedly been sacked by the new president, leaving the watchdog inquorate.

The oversight body was previously cited by the European Commission as evidence that the US offers the necessary level of protection of personal data to allow the Transatlantic Data Privacy Framework (TADPF) to be introduced.

Privacy campaigner Max Schrems, whose litigation in the EU courts twice brought down previous data sharing agreements, said the TADPF was “always built on sand”.

He today criticised the EU for accepting “executive promises that can be overturned in seconds” and warned that a crucial executive order enacted by Joe Biden could be revoked in weeks.

Mr Trump has ordered a review of all national security decisions made by his predecessor, including those central to the TADPF.

“I can hardly see that a Biden executive order that was forced upon the US by the EU and regulates US espionage abroad would survive in Trump’s logic,” Mr Schrems said.

He added: “While the arguments for the EU-US deal seem to fall apart, companies can rely on the deal as long as it is not formally annulled.

“However, given the developments in the US, it is more crucial than ever for any business or other organisation to have a ‘host in Europe’ contingency plan.”