NHS paid deposit for 400,000 protective gowns last Friday, but only 32,000 are believed to have been flown in

The NHS paid a deposit last Friday in an attempt to secure the delivery of 400,000 protective gowns – but only 32,000 are believed to have arrived in the first part of the delayed shipment.

Initial estimates were that a quarter of the order had been brought back from Istanbul by the RAF on Wednesday, but the Health Service Journal reported that the number of gowns received was 32,000, which amounts to only a few hours’ supply.

Air freight specialists who have seen images of the shipment told the Guardian they estimated it was less than 10% of the kit sought.

It is understood that a Turkish company approached the NHS on Thursday offering to supply 400,000 clinical gowns, and the order was placed within hours and an unspecified deposit paid the following day. The remainder of the payment was to be made when the whole order was completed, health sources said.

But insiders said the supplier was almost immediately hit with “an unexpected manufacturing delay”, raising questions about whether the company had the ability to deliver on the shipment as promised.

On Wednesday the health minister Nadine Dorries said there had been problems finding reliable sources of supply, and she criticised Labour for publicising a list of potential PPE suppliers.

The minister wrote: “Lots of companies making contact ‘I have 200 masks’ but when you dig deeper they don’t have any, they are just offering to act as agents and find some, for a commission.”

More than 100 NHS workers have died from coronavirus, and repeated exposure to the sick has made them one of the most vulnerable groups.

A succession of cabinet ministers promised the gowns would arrive imminently, starting with the communities secretary, Robert Jenrick, who said at Saturday’s daily press conference that the kit would arrive the following day.

On Wednesday night it emerged that the Department of Health had “strongly advised” Downing Street and Jenrick not to mention the consignment, but faced with growing concern over PPE shortages for frontline staff he did so anyway.

Gavin Williamson, the education secretary, and Oliver Dowden, the culture secretary, successively promised that the gowns would arrive on Monday, but they were delayed once again.

Initially the delay in securing the order was blamed on the failure to obtain export licences for the kit, with some applications being made on Monday. But once the approvals had been obtained there was at first no kit to pick up.

Eventually a shipment did reach Istanbul airport on Tuesday and it was flown out overnight on an Atlas A400M transport aircraft. But it was far less than the 84-tonne consignment that had been expected.