(Bloomberg) -- Senate Majority Leader Mitch McConnell on Tuesday blamed rising federal deficits and debt on a bipartisan unwillingness to contain spending on Medicare, Medicaid and Social Security, and said he sees little chance of a major deficit reduction deal while Republicans control Congress and the White House.

"It’s disappointing but it’s not a Republican problem," McConnell said in an interview with Bloomberg News when asked about the rising deficits and debt. "It’s a bipartisan problem: Unwillingness to address the real drivers of the debt by doing anything to adjust those programs to the demographics of America in the future."

McConnell’s remarks came a day after the Treasury Department said the U.S. budget deficit grew to $779 billion in Donald Trump’s first full fiscal year as president, the result of the GOP’s tax cuts, bipartisan spending increases and rising interest payments on the national debt. That’s a 77 percent increase from the $439 billion deficit in fiscal 2015, when McConnell became majority leader.

McConnell said it would be "very difficult to do entitlement reform, and we’re talking about Medicare, Social Security and Medicaid," with one party in charge of Congress and the White House.

"I think it’s pretty safe to say that entitlement changes, which is the real driver of the debt by any objective standard, may well be difficult if not impossible to achieve when you have unified government," McConnell said.

Politically Unpopular

Shrinking those popular programs -- either by reducing benefits or raising the retirement age -- without a bipartisan deal would risk a political backlash in the next election. Trump, during his campaign, promised he wouldn’t cut Social Security, Medicare or Medicaid, even though his budget proposals have included trims to all three programs.

McConnell said he had many conversations on the issue with former President Barack Obama, a Democrat.

"He was a very smart guy, understood exactly what the problem was, understood divided government was the time to do it, but didn’t want to, because it was not part of his agenda," McConnell said.

"I think it would be safe to say that the single biggest disappointment of my time in Congress has been our failure to address the entitlement issue, and it’s a shame, because now the Democrats are promising Medicare for all," he said. "I mean, my gosh, we can’t sustain the Medicare we have at the rate we’re going and that’s the height of irresponsibility."

Divided Government

McConnell said the last major deal to overhaul entitlements occurred in the Reagan administration, when a Social Security package including a raise in the retirement age passed with divided government.

McConnell said he was the GOP Senate whip in 2005 when President George W. Bush attempted a Social Security overhaul and couldn’t find any Democratic supporters.

"Their view was, you want to fix Social Security, you’ve got the presidency, you’ve got the White House, you’ve got the Senate, you go right ahead," McConnell said. The effort collapsed.

The Office of Management and Budget has projected a deficit in the coming year of $1.085 trillion despite a healthy economy. And the Congressional Budget Office has forecast a return to trillion-dollar deficits by fiscal 2020.

During Trump’s presidency, Democrats and Republicans agreed to a sweeping deal to increase discretionary spending on defense and domestic programs, while Trump’s efforts to shrink spending on Obamacare mostly fell flat.

Republicans also passed a 2017 tax overhaul projected to add more than $1 trillion to the debt over a decade after leaders gave up on creating a plan that wouldn’t increase the debt under the Senate’s scoring rules. However, McConnell, like many Republicans, has said growth will more than make up for the lost revenue.

House Minority Leader Nancy Pelosi of California reacted to McConnell’s comments Tuesday by saying the rising deficit is a direct result of the GOP tax cut enacted in December 2017.

“In budget after budget, congressional Republicans have exposed their cynical agenda: give massive, unpaid-for handouts to further enrich big corporations shipping jobs overseas and the wealthiest 1 percent, and stick seniors, children and families with the bill," Pelosi said in a statement. "Under the GOP’s twisted agenda, we can afford tax cuts for billionaires, but not the benefits our seniors have earned."

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