Joshua Gotbaum, director of the Pension Benefit Guaranty Corp., has a problem.

His agency, which guarantees private-sector pensions promised to 44 million Americans, is saddled with a huge deficit at risk of growing out of control.

The most direct way to close the gap is to substantially raise the premiums that firms pay to insure their pensions with the federal agency.

The agency has proposed not only increasing premiums but also setting prices in accordance with the perceived riskiness of the pension plans. Additionally, the agency wants Congress to give it authority to determine future premiums.

The moves are meant to help offset the eroding financial security of retirees. That erosion may only intensify once lawmakers — who just last week emerged from a bruising battle over the 2011 budget that nearly shut down the federal government — turn their full attention to entitlements such as Medicare and Social Security.

But there’s no guarantee the PBGC’s proposals will gain traction. Unveiled in President Obama’s 2012 budget request, they have already prompted strong objections from the business community.

Though pension insurance premiums account for a minuscule share of what it costs employers to pay for workers, businesses are warning that any increases would further shrink the dwindling pool of private employers that offer pension plans.

The Obama administration is searching for ways to bolster retirement security, which in recent decades has grown increasingly shaky for many working Americans.

Sixteen percent of private-sector employees have defined benefit plans, according to the Center for Retirement Research at Boston College. In 1980, 39 percent of private-sector workers were covered by pension plans. The median 401(k) balance for workers ages 55 to 64 is $78,000, the center said, which is hardly a secure nest egg. And about half of all workers have no retirement plan beyond Social Security.

Meanwhile, lawmakers may make changes to Social Security and Medicare that could lead to more out-of-pocket expenses for retirees.

Still, many firms are just recovering from the economic downturn after years of soaring costs for providing employee health-care coverage. So they recoil at the prospect of any increases in the cost of providing benefits to employees.

“Changes of the type and magnitude proposed by the administration would undermine the defined benefit pension system, [and] hinder the economic recovery,” read a letter to congressional leaders co-authored by 10 business groups, including the American Benefits Council and the Business Roundtable.

Gotbaum, a former investment banker who served in the Carter and Clinton administrations, said he respects the business community’s concerns. Still, he summed up those concerns in one word: “malarkey.”

“Since nobody wants a taxpayer bailout of the PBGC, premiums have to go up,” he said in a recent interview.

Gotbaum, who Obama appointed PBGC director in July, noted that pension insurance premiums account for only a penny or two of employee’s compensation costs, which nationally average $27.75 an hour, according to the Bureau of Labor Statistics.

Given that, Gotbaum said, a premium increase “is not going to be the deciding factor in whether people offer a pension plan or not. That is not going to happen.”

Opponents say they are concerned less about the size of any impending premium increase than about the process of determining it.

“It is the issue of turning over to the agency the authority to establish premiums when companies are compelled to deal with that agency,” said James Klein, president of the American Benefits Council.

At the same time, there is no denying the fiscal pressures facing the agency. The PBGC was established in 1974 to ensure that workers who held pensions at troubled firms did not lose all their retirement income — something that has happened repeatedly since the first pension plans were established by the railroads in the 19th century.

The agency receives no taxpayer money; instead it is funded by premiums charged to employers, the assets of pension funds they take over and investment returns. It insures pensions up to $54,000 a year for workers who retire at age 65, while intervening in troubled companies in an effort to keep their pensions viable.

Last year, the agency paid about $5.6 billion in benefits to 801,000 employees whose companies could not cover their pensions. It is also responsible for future payments to 700,000 workers who have yet to retire.

The agency is facing a $23 billion deficit, which Gotbaum has warned could explode to as much as $190 billion if several large and inadequately funded pension plans collapse.

Though the agency has no explicit government guarantee, there would be extreme political pressure to bail it out if it becomes insolvent — raising the stakes in the ongoing debate over how and when to raise premiums.

“At whatever point that people decide that premiums must go up, and they will,” Gotbaum said, “should they go up in a way that is fairer? Should they go up in a way that preserves defined benefit plans? That is the question.”