Financial markets reopen in Asia on Monday after Moody's Ratings announced Friday evening it was stripping the US government of its top credit rating, dropping the country to Aa1 from Aaa. The company, which trailed rivals, blamed successive presidents and congressional lawmakers for a ballooning budget deficit it said showed little sign of narrowing.

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The downgrade risks reinforcing Wall Street's growing worries over the US sovereign bond market as Capitol Hill debates even more unfunded tax cuts and the economy looks set to slow as President Donald Trump upends long-established commercial partnerships and re-negotiate trade deals. 

In a potential sign of things to come on Monday, 10-year Treasury yields rose as high as 4.49% in thin volumes on Friday and an exchange-traded fund tracking the S&P 500 fell 0.6% post-market.

"A Treasury downgrade is unsurprising amid unrelenting unfunded fiscal largesse that's only set to accelerate," said Max Gokhman, deputy chief investment officer at Franklin Templeton Investment Solutions.

"Debt servicing costs will continue creeping higher as large investors, both sovereign and institutional, start gradually swapping Treasuries for other safe haven assets," he added. "This, unfortunately, can create a dangerous bear steepener spiral for US yields, further downward pressure on the greenback, and reduce the attractiveness of US equities."

Michael Schumacher and Angelo Manolatos, strategists at Wells Fargo & Co., told clients in a report that they expect "10 year and 30 year Treasury yields to rise another 5-10 basis points in response to the Moody's downgrade."

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A 10 basis point increase in the 30-year yield would be enough to lift it above 5% to the highest since November 2023 and closer to that year's peak, when rates reached levels unseen since mid-2007.

While rising yields typically boost a currency, the debt worries may add to skepticism over the dollar. A Bloomberg index of the greenback is already close to its April lows and sentiment among options traders is the most negative in five years.

'Loss of Confidence'

European Central Bank President Christine Lagarde told La Tribune Dimanche in an interview published on Saturday that the dollar's recent decline against the euro is counterintuitive but reflects "the uncertainty and loss of confidence in US policies among certain segments of the financial markets."

Rising Treasury yields would also complicate the government's ability to cut back by running up its interest payments, while also threatening to weaken the economy by forcing up rates on loans such as mortgages and credit cards.

US Treasury Secretary Scott Bessent downplayed concerns over the US's government debt and the inflationary impact of tariffs, saying the Trump administration is determined to lower federal spending and grow the economy.

Asked about the Moody's Ratings downgrade of the country's credit rating Friday during an interview on NBC's Meet the Press with Kristen Welker, Bessent said, "Moody's is a lagging indicator — that's what everyone thinks of credit agencies."

In a move that may help temper some of the negative market sentiment, President Trump said over the weekend he'll have a phone call with Russian President Vladimir Putin on Monday morning to discuss how to stop the war in Ukraine.

Moody's move was anticipated by many given it came when the federal budget deficit is running near $2 trillion a year, or more than 6% of gross domestic product. The US government is also on track to surpass record debt levels set after World War II, reaching 107% of GDP by 2029, the Congressional Budget Office warned in January.

Moody's said it expects "federal deficits to widen, reaching nearly 9% of GDP by 2035, up from 6.4% in 2024, driven mainly by increased interest payments on debt, rising entitlement spending, and relatively low revenue generation."

Despite such sums, lawmakers will likely continue work on a massive tax-and-spending bill that's expected to add trillions to the federal debt over the coming years. The Joint Committee on Taxation had pegged the total cost of the bill at $3.8 trillion over the next decade, though other independent analysts have said it could cost much more if temporary provisions in the bill are extended.

Analysts at Barclays Plc said in a report that they did not expect the Moody's downgrade to change votes in Congress, trigger forced selling of Treasuries or have much impact on money markets. Treasuries have often rallied after similar actions in the past. 

"Credit downgrades of the US government have lost political significance after S&P downgraded the US in 2011, and there were limited, if any, repercussions," said Michael McLean, Anshul Pradhan and Samuel Earl of Barclays. 

Around the same time Moody's was announcing its decision, the US Treasury was reporting China had reduced its holdings of Treasuries in March. While that may further encourage speculation the world's second largest economy is lowering its exposure to US debt and the dollar, Brad Setser, a former Treasury official, said on X that the data suggested "a move to reduce duration than any real move out of the dollar."

Despite the recent trade tensions and worries over fiscal profligacy, the Treasury statistics suggested foreign demand for US government securities remained strong in March, indicating no signs of a revolt against American debt.

Still, traders will be hard at work early again on Monday, just a week since they had to react quickly to weekend news of an improvement in trade relations between the US and China.