Apple is widely expected to reveal a mobile payments system alongside the iPhone 6 at its press event on September 9th. The system — supposedly designed to take on Google Wallet, Isis, Paypal, and others — would allow you to use your phone to pay for items at the cash register, and it appears Apple's gained some strong allies in its quest. Bloomberg reports that Visa, MasterCard, and American Express have agreed to work together with Apple on the rumored payments system. Recode and The Information previously reported that American Express and Visa, respectively, had reached agreements with Apple.

The reports, which cite sources familiar with the matter, do not go into the nature of the agreements. Visa, MasterCard, and American Express would be a major coup for Apple's mobile payment efforts, but the company will have to make partnerships numerous other retailers and banks if it it hopes to make a truly comprehensive and compelling alternative to traditional credit cards. Many retailers still lack point-of-sale systems that can accept payments using NFC chips built into phones, and if Apple can't convince companies to make the costly upgrades to support the new payments system, it will likely fail to catch on.

But does Apple also have retailers on board?

Even with the three major credit card companies on board, it's possible that Apple's mobile payment system may not be the same as using a true credit card. Other mobile payment systems, such as Google Wallet and wireless carrier-backed Isis, use digital pre-paid credit cards that can be loaded with any other card in order to make purchases — a nifty work-around that makes it appear that all credit cards are supported. It's also unclear how a future iPhone will send transaction data. Bloomberg and Wired both suggest that Apple will use Touch ID in conjunction with a new NFC chip in its next phone to authenticate purchases, but we'll find out for sure on September 9th.

Update August 31st, 2014, 4:32PM ET: A new Bloomberg report builds on Recode's article from earlier today, adding that MasterCard and Visa, in addition to American Express, have reached agreements with Apple. This article has been updated appropriately.