Amazon and Microsoft are the last competitors standing in the Pentagon’s winner-take-all competition for a $10 billion cloud services contract, the Defense Department said.

The announcement eliminates Oracle and International Business Machines. Defense Department spokeswoman Elissa Smith said only (amzn, -0.23%)Amazon and (msft, -0.11%)Microsoft met “the minimum requirements” for the JEDI project.

The winnowing of the field came as the Pentagon said it’s determined that the acquisition process for the contract wasn’t tainted by alleged conflicts of interest, allowing final selection to move ahead, according to Smith.

Amazon and Microsoft have been widely viewed as front-runners in part because they have obtained higher-level federal security clearances.

Representatives from Oracle, Microsoft, and IBM declined to comment. A representative from Amazon didn’t immediately respond to a request for comment.

The Pentagon had initially said it would choose a winner this month, but after investigations and a protracted legal battle, the soonest the contract will be awarded is mid-July, according to Smith. She also revealed that alleged unethical conduct by a former Defense Department employee has been referred to the department’s inspector general.

The Joint Enterprise Defense Infrastructure cloud—or JEDI, an acronym intended to evoke Star Wars imagery—is intended to serve as the primary data repository for…