President Barack Obama asks for revised blueprint for building detainee facility in U.S. as time runs down on one of his longtime priorities.

The Pentagon’s latest cost estimate for closing the prison at Guantanamo Bay, Cuba, and building an alternative in the U.S. topped a half billion dollars, prompting the White House to reject it and send the plan back for revisions, according to administration officials. The cost dispute marked a setback for a top priority of President Barack Obama, and helps account for the administration’s delay in submitting a plan to Congress for closing Guantanamo. The Pentagon estimated it would require as much as $600 million to close the prison, including a one-time capital investment of as much as $350 million in construction costs, according to officials familiar with the Pentagon plan, which hasn’t been released publicly. The annual cost of operating the Guantanamo detention facility now is about $400 million. Under the Pentagon plans, operating a U.S.-based facility would run something less than $300 million, after the one-time costs, a defense official said. The estimated costs prompted Mr. Obama to reject the plan during a meeting with Defense Secretary Ash Carter last month, and to send it back to the Pentagon, U.S. officials said.

Mr. Obama’s move further pushed back the submission of a plan to Congress, another in a series of delays since the White House said it would send the proposal to lawmakers this past summer. The plan being drafted by the Pentagon is likely to be Mr. Obama’s last attempt before leaving office to get legislative approval for closing Guantanamo. The president is already facing strong bipartisan opposition in Congress to his longtime goal of closing the detention facility, and the White House anticipated that lawmakers would balk at the new cost estimates, officials said. The estimates also threatened to undermine one of Mr. Obama’s top arguments for closing Guantanamo: that it is too costly to maintain.

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