The Navy is estimating its maintenance and operations budget is on course for an $8.6 billion budget shortfall by the end of 2013, and officials are planning to close the gap by shutting down four air wings, canceling or delaying deployments of several ships, docking two destroyers and deferring a planned humanitarian mission by the service’s premier medical ship to Latin America, according to an internal memo obtained by the Washington Guardian.

The memo from Navy Secretary Ray Mabus, dated Friday and sent to Navy managers, is the latest political effort by the Navy to address budget shortfalls caused both by the inability of Congress to enact a formal 2013 budget and the decision by lawmakers and the White House to let automatic spending cuts known as the sequestration take effect late last week.

The Mabus memo states $4.6 billion of the projected shortfall is due to the $85 billion in government-wide sequester cuts while $4 billion can be attributed to the fact that Congress appears intent on funding the government at 2012 levels using “continuing resolutions” rather than enact the Pentagon’s 2013 budget request.

The financial toll will leave Navy ships pier-side at their respective home ports and will cut necessary training for Navy personnel not deployed or soon-to-be deployed, the memo states. The immediate cuts will also lead to the laying off of temporary personnel, imposing a civilian hiring freeze and reducing aviation flight training, Navy officials said in interviews.

Navy officials spread word of the severity of cuts as they continue to negotiate with Congress for flexibility to temporarily defer some of the cuts.

“We’re continuing to work with Congress to move money but as of yet we have no authority,” Navy spokeswoman Lt. Courtney Hillson said. “We had to take action now to reduce spending. It significantly effects our maintenance and operational” activities.

Republicans proposed this week to restore roughly $7 billion to operations and maintenance accounts for all military branches. That bill would preempt the continuing resolution expected to expire March 27.

But it’s not a certainty. Just days after the sequester cuts took effect across government, Republicans and Democrats continue to point fingers and assign political blame with little sign of compromise on the horizon.

Some conservatives dismiss as scare tactics the recent spate of Pentagon press conferences and budget memos warning of the consequences of budget cuts on military readiness.

James Carafano, a senior defense analyst with the Heritage Foundation, said the Mabus memo was designed to apply political pressure to roll back certain cuts even though the service should have long ago prepared for leaner times and began trimming some nonessential spending. He specifically cited a Navy experiment known as the Green Fleet in which the Navy has retrofitted some ships to user cleaner burning biofuels.

“If Mabus really cared about maintenance and operations and readiness, he wouldn’t have dumped millions into green energy programs the Navy doesn’t need,” Carafano said. “…DOD lacks credibility coming out so late on complaining about sequester.”

But Navy officials insist their latest memo is an effort to take specific actions to avoid running a deficit while meeting its most critical national security obligations.

The Friday memo said the Navy would stand down its “carrier air wing two (CVW-2)” in April, adding that the branch will initiate “preparations to gradually stand down flying in at least three additional air wings with two more air wings being reduced to minimum safe flying levels by the end of the year.”

Mabus added the Navy will “cancel or defer the deployments of up to six ships to various areas of responsibility throughout the month of April.” The memo does not specify which ships.

The memo also revealed that the USNS Comfort, the Navy’s premier medical ship, has delayed its deployment to Central and South America on a planned humanitarian mission. This deferment also includes “supporting ships, Seabees and medical units,” that were part of the mission, according to the memo. In a further cost-cutting move, the USNS Comfort moved last week from the harbor in Baltimore that it has called home for 26 years to the shipyards in Norfolk, Va.

The Navy will also “lay up four combat logistics force units,” in Pacific Command starting in April, Mabus wrote.

Other directives include returning a number of destroyers home from overseas. The USS Shoup is expected to return back to her home base in Everett, Wash., while the USS Thach will also be returning back to her home port.

On Friday, Defense Secretary Chuck Hagel warned Pentagon reporters that sequestration will harm military readiness. “This is the security of the United States of America we’re talking about,” Hagel said. “We will do what is necessary and what it takes to assure that security.”

Hagel added that planned cuts to the Navy’s civilian workforce will be “painful” but that he is also concerned about the “readiness that these cuts will have across our force.”

Navy readiness is already suffering because of these cutbacks and could “affect training, particularly people who are not deploying, they will not be a priority and they will not get the same training,” added Hillson, the Navy spokeswoman.