The US Navy has revealed that it is unable to separate its custom-built cloud system from the Microsoft Azure environment without conducting a full rebuild.

As reported by The Register, the Navy shared a sole-source justification letter detailing why it had awarded Microsoft the "Strategic Cloud Platform - Enterprise Mission Integration" contract.

In the partially redacted attached document, the Navy states that the contract was for the "lift and shift" of its existing NAVSEA cloud environment, a "fit-for-purpose designated cloud platform that provides access to the Navy and Department of Defense (DoD) programs."

The US DoD is now known as the Department of War (DOW), according to an executive order signed by President Donald Trump. However, an official name change requires Congressional approval.

According to the document, Microsoft was selected as "only one awardee is capable of providing the supplies or services required."

In order for the NAVSEA environment to continue "enterprise mission integrations operations," it needs to use Azure Data Transfer, Azure Kubernetes Service (AKS), Azure Structured Query Language (SQL) platform-as-a-service (PaaS), Azure Key Vault, Azure Monitor, and ExpressRoute networking provided within the Microsoft environment, as it was designed within the Microsoft GovCloud offering.

The document notes: "In order for another CSP to host the NAVSEA environment, the Government would need to re-engineer the solution from the ground up. This will require the integration of a new cloud environment and re-engineering of operational applications that support Defensive Cyber Operations (DCO), which would result in a break in service and inevitable mission failures."

It adds: "The only CSP capable of performing the transition of NAVSEA Cloud at the required level of quality is Microsoft. Re-architecting, re-engineering, and refactoring of any of the critical cloud service offerings from Microsoft to any other CSP would not meet the Government’s need for compatibility."

This has also been established, according to the Navy, through outreach to all four Joint Warfighting Cloud Capability (JWCC) CSPs - including Amazon Web Services, Google, and Oracle.

In the future, NAVSEA will build future cloud infrastructure deals using open containerization standards to avoid being tied to a single cloud provider.

Microsoft was notably under fire earlier this year after reports emerged that a "Digital Escorts" program enabled Microsoft to use Chinese coders remotely supervised by US contractors to support DOW cloud systems. Earlier this month, US Secretary of Defense/War Pete Hegseth shared a statement confirming that this had been stopped.

The JWCC program, valued at $9 billion, was awarded in December 2022 to Amazon Web Services (AWS), Microsoft Azure, Google, and Oracle. It replaced the previous Joint Enterprise Defense Infrastructure (JEDI) contract, which was announced in 2018, and is set to be worth $10bn over ten years.

In July of this year, the Defense Information Systems Agency revealed it was looking for new partners to join the program, specifically smaller providers.