A new clash over retirement benefits has come to a head following President Obama’s decision to unilaterally protect up to 5 million illegal immigrants from deportation.

The White House now acknowledges that many of the illegal immigrants spared from deportation under Obama’s sweeping executive action will become eligible for Social Security and Medicare benefits once they reach retirement age.

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The conservative backlash has been swift and will certainly extend into a GOP Congress’ deliberations in 2015 over how to limit the reach of the president’s immigration blueprint.

A central argument in Obama’s defense of the most extensive overhaul to the immigration system in decades was that those given reprieves from deportation would not qualify for Obamacare benefits. The president reminded critics that Dream Act-eligible immigrants previously granted deportation deferrals could not enroll in federal health exchanges.

However, Obama was less eager to wade into the debate about what to do with newly protected immigrants now paying into Social Security. He didn’t address the matter while outlining his immigration plan in a prime-time address to the nation, but White House aides later confirmed GOP suspicions about how Obama’s unilateral move would affect retirement benefits.

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Analysts said that Republicans would use the admission to argue the president is misleading the public about the details of his immigration action.

“It is a bit of surprise,” said Michael Tanner, a senior fellow at the Cato Institute who focuses on entitlement programs. “For a long time, there was an argument made by the administration that [undocumented immigrants] would not be eligible for such benefits. It does seem to be a contradiction.”

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For Republicans, this debate is about far more than just Social Security. It fits into the broader narrative of painting the president as unwilling to spotlight an unpopular provision of his agenda until after it has been enacted.

“It’s Obamacare all over again, ‘If you like your doctor, you can keep your doctor,” one House GOP leadership aide told the Washington Examiner. “Obama was very clear on this issue. He said no benefits. What the president says just isn’t credible. That couldn’t be any more obvious by now.”

The administration says Obama’s move is sound fiscal policy, that it makes sense to grow the tax base. They also argue that it would be unfair to force people to pay into Social Security and not reap the same benefits as everybody else.

Immigrants would have to work at least 10 years to qualify for Social Security and Medicare benefits, administration officials said, and Obama’s executive action could always be reversed by any of his successors.

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Though quiet about the Social Security implications of the president’s latest executive action, the White House has long argued that comprehensive immigration reform would strengthen the long-term outlook of entitlement programs.

“Over 500 days ago, the United States Senate passed legislation with bipartisan support to improve border security, streamline the immigration process and establish a firm but fair path to citizenship,” Vice President Joe Biden wrote in an op-ed this week in Irish Central. “It would be an absolute game-changer for our economy, adding $1.4 trillion to our economy and reducing the deficit by nearly $850 billion over 20 years, and extending the solvency of Social Security by another two years.”

However, some fiscal hawks say that any short-term benefit of having more people paying into Social Security would be eclipsed by the burden of paying out benefits to potentially millions of additional people.

Republicans also point to the illegal immigrants not yet covered by Obama's unilateral action.

“It is also important to keep in mind that while 5 million [illegal immigrants] benefit affirmatively from executive amnesty with work permits, photo ID’s and social security numbers, almost all of the other 7 million illegal immigrants continue to remain functionally immune from enforcement,” said Stephen Miller, a spokesman for Sen. Jeff Sessions, R-Ala. “The problem for American workers will be compounded even more when the amnesty produces the ensuing wave of new illegal and chain migration.”

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