TOKYO -- Japanese Prime Minister Sanae Takaichi sought to reassure financial markets over her government's fiscal policy, pledging on Monday to respond "flexibly" to economic and market conditions while giving little indication that she will shift from her expansionary spending agenda.

The change in tone comes as Takaichi faces growing market concern over Japan's fiscal position and pressure from the U.S. to avoid reflationary messages that could further weaken the yen. But analysts said her remarks offered little evidence of a fundamental change in policy.

In her speech marking the opening of an extraordinary Diet session, Takaichi said the government would adjust fiscal policy "flexibly and swiftly" according to economic and market conditions.

Tokyo would determine annual bond issuance by taking into account interest rates and other market conditions, she said, adding that her government would "build market confidence in the government through orthodox policy measures." The comments represent an effort by Takaichi to balance her commitment to an expansionary economic agenda that aims to soothe the cost of living caused by the impact of inflation, with growing concerns over the yen and Japan's already strained public finances.

Before her policy speech, she addressed the arrest on Sunday of a U.S. Marine on suspicion of robbing and murdering a Japanese woman in Okinawa, after which Japan lodged a formal protest with the U.S.

"The occurrence of such an extremely brutal and vicious incident is extremely regrettable," Takaichi said.

She reiterated her statement disclosed on Sunday, saying, "The government of Japan strongly protests to the U.S. side and strongly seeks maximum cooperation with the investigation," as well as the tightening of discipline and thorough measures to prevent a recurrence.

The arrest comes at a politically sensitive moment for Takaichi's conservative government. A candidate backed by her ruling party won the Okinawa gubernatorial election last month, ending 12 years of rule by governors opposed to the heavy concentration of U.S. military bases in the prefecture.

Okinawa hosts the bulk of the roughly 18,000 U.S. Marines stationed in Japan. The islands remained under U.S. administration for nearly three decades after World War II before being returned to Japanese control in 1972.

In her expansionary spending agenda, Takaichi has championed 370 trillion yen ($2.3 trillion) in public and private investment by 2040 aimed at supporting growth and easing cost-of-living pressures and has pushed for a temporary cut in the consumption tax on food. Supporters of Takaichi's economic policy argue that its emphasis on strategic investment would raise Japan's potential growth by stimulating demand in the short term while expanding the economy's productive capacity over time.

But investors have become increasingly concerned that additional fiscal stimulus could add to inflationary pressures and further weaken Japan's fiscal position.

Those concerns have been reflected in the bond market. In late September, the yield on benchmark 10-year Japanese government bonds rose to a three-decade high of 3.115% as a sell-off accelerated amid inflation concerns triggered by higher oil prices related to the U.S. war with Iran. Bond prices generally move inversely to yields.

Takaichi is also facing pressure from Washington over the yen. U.S. Treasury Secretary Scott Bessent has repeatedly voiced concerns about the currency's persistent weakness and urged Tokyo to avoid reflationary messages that could keep it under pressure.

Last month, Bessent challenged currency traders betting against the yen, saying "I am the house now," using a casino metaphor.

Finance Minister Satsuki Katayama told Nikkei last week that the government was united in its view that Japan's reflationary policy was over, echoing Bessent's comments.

But Takahide Kiuchi, executive economist at Nomura Research Institute, said in an analysis of a widely reported draft of Takaichi's speech that the prime minister's comments do not amount to a fundamental shift in fiscal policy and were unlikely on their own to dispel market concerns.

While the speech was "peppered with remarks aimed at reassuring markets and maintaining market confidence," Kiuchi said, "this does not necessarily mean that policy will actually be adjusted out of consideration for financial markets." He warned that continued expansionary fiscal and monetary policies could put further downward pressure on the yen and Japanese government bond prices, exacerbating inflation and pushing long-term interest rates higher, with potentially negative consequences for the economy.