Moody's is the last of the big three credit rating firms that still bestows the cherished "triple-A" rating on the US, which indicates US government bonds are among the safest investments on earth, Axios reported.

Fitch Ratings stripped the US of its AAA rating in August, citing the debt ceiling fight and governance issues.

S&P Global downgraded the US from AAA back in 2011 after a similar debt ceiling fight.

The House Republican conference has been unable to advance key budgetary bills amid divisions between Speaker Kevin McCarthy and right-wing factions demanding deep budget cuts.

They're preparing one more push to try to fund the government before October 1.

In a note published Monday afternoon, Moody's spotlighted the political chaos that surrounds budgeting decisions in Washington, suggesting that such brinksmanship is inconsistent with its top Aaa rating.

"Fiscal policymaking is less robust in the US than in many Aaa-rated peers, and another shutdown would be further evidence of this weakness," they wrote.

"After having negotiated a contentious bipartisan debt limit deal in June, US Congress is yet again renewing internal party disagreements that threaten a government shutdown and clearly reflect the political hurdles to US fiscal policymaking," they said.

The risk of such fiscal hijinks has grown as the US government's public debt load has increased to roughly 100% of GDP in the aftermath of the COVID crisis, Moody's said.

Moody's seems to be warning that if a government shutdown ensues, the US could kiss its last claim to triple-A status goodbye.