The European Central Bank (ECB) is throwing a wrench into Apple's plans, claiming iPhones might not be ready for the digital euro. A key ECB figure believes Apple's current payment system lacks the muscle to handle a future digital currency.

In a letter to the EU's antitrust chief, ECB board member Piero Cipollone argued that Apple's proposed changes wouldn't grant full access to the phone's secure element (SE), a high-security chip that acts like a digital vault for financial information. This limited access, Cipollone fears, could cripple offline payments for the digital euro.

But security isn't the only concern. Cipollone worries that Apple's proposed system wouldn't offer the same smooth and secure transactions users experience with Apple Pay. He argues that this creates an uneven playing field for other payment options, potentially hindering a seamless digital euro experience for iPhone users.

Cipollone also takes aim at the EU's recent antitrust investigation into Apple, arguing it doesn't address limitations on a key technology: Near-Field Communication (NFC). NFC allows for contactless payments, which Cipollone sees as crucial for the digital euro, especially for person-to-person transactions.

The ECB, however, has a solution in mind. Proposed regulations for the digital euro call for phone makers and service providers to offer open access to the secure element in their devices. This unrestricted access, argues Cipollone, is vital for user-friendly digital euro payments on mobile phones.

With the European Commission laying the groundwork for a potential digital euro and the ECB gearing up for a two-year preparatory phase, Apple needs to adapt its iPhone payment system to avoid being left behind in the digital currency revolution.