Oil Falls on Iran Deal Optimism, Yen Strengthens: Markets Wrap

(Bloomberg) — Oil fell and Treasuries rose after President Donald Trump said fresh US-Iran talks would begin Monday, boosting optimism the two sides will reach a deal to reopen the Strait of Hormuz. Asian stocks fell as South Korean chipmakers tumbled.

Brent for October slid as much as 7.3% to $81.55 a barrel after Trump said he’d agreed to call off a massive attack on Iran as allies in the Middle East, including Saudi Arabia, asked him to pursue a deal instead. Oil was also weighed down by another small increase by major OPEC+ nations to their production quotas.

Treasuries rose across the curve as oil’s decline eased inflation concerns. The benchmark 10-year yield dropped four basis points to 4.69%, after rising to the highest since January 2025 last week. Gold climbed as much as 0.9% to about $4,080 an ounce.

The yen strengthened for a fourth day, building on its gains late last week. The Japanese currency advanced as much as 1.4% to 155.23 per dollar with traders remaining on alert for further intervention after Japan and the US warned they were ready to wade into the market again after coordinated action last week. Bloomberg’s gauge of the dollar fell, with the yen contributing the most to that move.

Monday’s market gyrations came after days of escalating tensions that saw the US threaten to hit the Islamic Republic “very hard” in a bid to end a conflict now in its sixth month. A supply squeeze triggered by the war drove up fuel costs, stoking fears of another inflation spike and unsettling investors. Focus is also returning to the artificial intelligence theme after a week of violent swings culminated in a sharp rebound for chip stocks after a rout in semiconductors earlier.

“If we get something concrete on a peace deal, or more importantly the reopening of the strait of Hormuz, then we could see some strong relief rallies across the market,” said Nick Twidale, chief market analyst at AT Global Markets. “For now it feels we will continue to see volatility across different markets, especially as AI trade remains the dominant theme for equities.”

A regional gauge of chip stocks fell 0.7% as Samsung Electronics Co. and SK Hynix Inc. both tumbled about 7%, offsetting gains in Japanese semiconductor companies such as Renesas Electronics Corp. and Kioxia Holdings Corp. Alibaba Group Holding Ltd. rose 5.5% in Hong Kong after releasing its latest flagship AI model, with performance claims putting it alongside global leaders like Anthropic’s Fable.

On Friday, China’s DeepSeek rolled out a public beta application programming interface, or API, for its flagship artificial intelligence model, V4 Flash, touting advancements in agentic abilities.

South Korea’s Kospi Index, a bellwether for AI investments, fell more than 4%, after surging a record 18% on Friday. With the Nikkei 225 Stock Average also slipping about 2%, the broader MSCI gauge of Asian shares fell 0.8%.

Sentiment stabilized with futures contracts for the Nasdaq 100 Index rising 0.9%.

Meanwhile, Trump suggested a deal on reopening the Strait of Hormuz may be close, and said he would also continue to pursue a path to end Iran’s nuclear program.

Iranian Foreign Minister Abbas Araghchi said Sunday that negotiations between Iran and Oman are in the final stages. The two countries that flank the strait are discussing a new route through it, but the talks don’t cover whether the strait will be closed or open.

“It would have been the biggest attack since World War II,” Trump said Sunday to reporters on Air Force One. “We’re just going to see whether or not we can make a deal.”

Elsewhere, markets remain on high alert for more joint intervention by Japan and the US on Monday after coordinated operations in Tokyo and New York last week triggered a dramatic rebound in the currency.

Japan’s Ministry of Finance said it conducted a yen-buying operation on July 31, US time, in coordination with the US Department of Treasury and wouldn’t hesitate conducting further joint intervention. Trump told reporters on Sunday that the move was “a signal of friendship.”

Treasury Secretary Scott Bessent said the US stepped in to help fight “disorderly” movements in the yen and is ready to keep helping Japan. Bessent also pointed to a Federal Reserve facility Japan could use.

Japan confirmed it bought yen on Friday and would use the facility in the future, according to Finance Minister Satsuki Katayama in a statement. In a social media post, Bessent said he supported the move and would encourage the facility to be upsized.

“For a week probably, we can see more choppiness and probably more temporary yen strengthening,” said Julia Wang, North Asia chief investment officer at Nomura International. “But we do think this does not change the actual direction for dollar-yen and probably will continue higher once the intervention is behind us.”

Some of the main moves in markets:

Stocks

S&P 500 futures rose 0.5% as of 11:57 a.m. Tokyo time Japan’s Topix fell 2.2% Australia’s S&P/ASX 200 fell 0.3% Hong Kong’s Hang Seng rose 0.3% The Shanghai Composite fell 0.6% Euro Stoxx 50 futures rose 0.8% Currencies

The Bloomberg Dollar Spot Index fell 0.2% The euro was little changed at $1.1532 The Japanese yen rose 0.6% to 156.47 per dollar The offshore yuan was little changed at 6.7525 per dollar Cryptocurrencies

Bitcoin fell 0.6% to $63,056.83 Ether fell 1.1% to $1,861.78 Bonds

The yield on 10-year Treasuries declined four basis points to 4.69% Japan’s 10-year yield advanced 2.5 basis points to 2.815% Australia’s 10-year yield was little changed at 4.93% Commodities

West Texas Intermediate crude fell 6% to $79.63 a barrel Spot gold rose 0.4% to $4,063.40 an ounce This story was produced with the assistance of Bloomberg Automation.

–With assistance from Matthew Burgess, Elaine Lai and Winnie Hsu.

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