America’s top credit rating is likely to face downward pressure in the years to come because of a swelling national debt load and widening budget deficits, Moody’s Investors Service said.

The U.S., which is rated Aaa with a stable outlook, faces “downward pressure in the long-term, due to meaningful fiscal deterioration,” Moody’s analysts Sarah Carlson and Yves Lemay wrote Friday in a report.

“Rising entitlement costs and rising interest rates will cause the U.S.’s fiscal position to further erode over the next decade, absent measures to reduce those costs or to raise additional revenues.”

The report comes as President Donald Trump signed a two-year budget agreement that will boost federal spending by almost $300 billion.

The nonpartisan Committee for a Responsible Federal Budget said the deal would add a net $320 billion to deficits over a decade, or $418 billion when factoring in additional interest costs. That’s on top of an estimated $1 trillion added to the deficit over 10 years by the Republican tax-cut legislation passed in December.

“The recently-agreed tax reform will exacerbate and bring forward those pressures,” the Moody’s analysts wrote. Offsetting the debt burden, they said, is America’s strong, wealthy and dynamic economy. Its role in the global financial system is “unmatched.”

S&P Global Ratings is the only credit-rating company that doesn’t give the U.S. a top score. It downgraded the U.S. to AA+ in August 2011 after a debt-ceiling standoff.