A $10 billion contract to be the exclusive cloud computing provider for the Pentagon’s Joint Enterprise Defense Infrastructure (JEDI) project has been narrowed down to Amazon and Microsoft. Oracle and IBM are officially out of the running after the Defense Department concluded they do not meet “minimum requirements” for working with highly classified and sensitive military data, according to The New York Times.

Oracle and IBM have challenged the process, contending that the contract is unfairly slanted in Amazon’s favor and locks the military into a single cloud provider for a decade, but the Pentagon has now formally ruled them out of contention. Google previously opted out of the bidding process due to employee backlash and concerns the work wouldn’t jive with the company’s artificial intelligence (AI) principles.

While a decision was initially expected this month, delays caused by internal investigations and legal challenges have pushed a final decision back to July, at the earliest. The Defense Department said it found no conflicts of interest, as alleged in a lawsuit by Oracle. A Pentagon employee who was hired by Amazon and later returned to the Pentagon was involved in the JEDI project during its early stages and had “no adverse impact on the integrity of the acquisition process,” a Pentagon spokesperson told The New York Times.

With the top two cloud providers now vying for the largest federal IT project to date, it’s unclear how much of the battle between cloud giants will be made public. Amazon’s previous work with the Central Intelligence Agency and dominant share of the cloud market is expected to give it a leg up on the competition.

Amazon and Microsoft have obtained the necessary high-level federal security clearances, but Microsoft is playing catch-up, having bolstered its government cloud security authorizations with significant upgrades to Azure in October.

Microsoft employees have also protested the company’s bid on the JEDI contract, accusing the company of betraying its AI principles, but the company is moving forward nonetheless. While Google withdrew its bid after a similar outcry, it also conceded that some portions of the contract were outside the scope of Google’s security certifications.

Although other areas of the federal government and most enterprises are adopting strategies that diversify their efforts in the cloud with multiple vendors, the Defense Department is determined to award the 10-year contract to one cloud vendor.