Good morning and welcome back to FirstFT Asia. In today’s newsletter:

• Oil shock tests Japan’s Sanae Takaichi

• China’s petitioners battle to be heard

• The radio station sending mystery messages to Iran

We begin in Tokyo, where oil market turmoil is posing the first major challenge to Sanae Takaichi since her landslide election victory last month. Here’s what to know.

Recession risk: The war in Iran has thrown Japan’s heavy reliance on energy imports, particularly from the Middle East, and its vulnerability to energy market volatility into stark relief, analysts said. The country imports almost all of its energy and much of its food, meaning that turmoil in energy markets, combined with prolonged weakness in the yen, could quickly translate into higher inflation.

As crude oil prices surged past $100 a barrel this week, economists warned of the fallout for Japan’s economy, including the longer-term risk of tipping the country into recession. “There is a risk of stagflation in Japan” if the price of oil continues to rise, said Takahide Kiuchi, an economist at the Nomura Research Institute.

Takaichi’s dilemma: The upheaval comes at a critical time for Takaichi, who won a historic election victory last month on pledges to alleviate the pain of rising food prices. She told parliament on Monday that the government was considering dipping into Japan’s strategic oil reserves to ensure petrol prices “do not rise to levels that cannot be borne by households”. Read more about the war’s implications for Japan.

• Latest Middle East developments: Iran’s foreign minister denied that the country has planned to attack the US navy, after Donald Trump warned against placing mines in the Strait of Hormuz. Meanwhile, Brent crude chalked up its biggest one-day drop in four years yesterday in another volatile session. Follow our live blog for more updates.

• The contest for gas: Asian and European buyers are battling to source liquefied natural gas after the war choked off shipments through the Strait of Hormuz

• Iran war endgame: Trump has failed to articulate US objectives in Iran but said the conflict will be over “very soon”. Here’s how it could unfold.

• Inside the oil market chaos: How traders at one London firm coped with one of the most volatile days the oil market has ever seen.

• Opinion: Even if the war ends quickly, governments — especially in Asia — will need to prioritise the security of their energy lifelines, writes Amrita Sen.

Here’s what else we’re keeping tabs on today:

• Economic data: The US publishes February inflation figures.

• FT webinar: Sign up for today’s exclusive FT subscriber webinar about the Middle East war. Columnists Kim Ghattas, Edward Luce, Katie Martin and Gideon Rachman will join Alec Russell, foreign editor, to dissect the political, military and diplomatic calculations behind the conflict.

Five more top stories

1. China has called in executives from Europe’s two largest shipping companies to complain about extra freight charges and the suspension of services to the Middle East as the war in Iran disrupts trade. Here’s what we know about Beijing’s talks with Maersk and Mediterranean Shipping Company.

• Chinese trade: China’s exports surged 21.8 per cent year on year in dollar terms in January and February, putting its economy on course for another year of record trade surpluses.

• Indian oil imports: A US waiver allowing India to buy Russian oil that is already at sea will bring immediate but very limited relief to Indian refiners facing a supply shock in the Middle East.

2. Standard Chartered plans to double the number of private bankers catering to wealthy Chinese in Singapore. The expansion comes despite increased scrutiny of flows from China to the city-state after a series of high-profile money-laundering scandals. Read more about StanChart’s Singapore plans.

3. Amazon kicked off the busiest day on record for US corporate bond sales with plans to raise nearly $50bn as borrowers rushed to take advantage of calmer markets after Trump hinted that the Iran war could end soon. The ecommerce giant’s bond sales mark the latest intensification of a borrowing binge by Big Tech companies to fund AI infrastructure.

4. The largest rare earths producer outside China has struck a supply deal with Japan at the same minimum price that Washington last year guaranteed a US supplier, as countries seek to avert a supply crunch after Beijing restricted exports of the key materials. Read more about Tokyo’s deal with Australian mining group Lynas Rare Earths.

5. Citadel and ExodusPoint are among the big-name hedge funds to have been stung by the market fallout from war in the Middle East. One portfolio manager who focuses on macro trades said that Wall Street believed Trump would “drop a few bombs” and then exit the conflict. “But it’s gotten far uglier than people thought.”

News in-depth

In a country with no free press or independent judiciary, China’s citizen petitioning system operates as a social pressure valve for the country’s desperate and downtrodden, offering a rare channel to challenge alleged abuses of power by lower authorities. For Beijing, the centuries-old system offers a glimpse at nascent unrest, even as authorities are keen to ensure disputes are not widely publicised. Joe Leahy reports from the Chinese capital on the petitioners battling to be heard.

We’re also reading . . . 

• App romance: Hinge is posting growth in a sector dogged by shrinking audiences and online dating fatigue. Its CEO explains why.

• French politics: Elections in French cities this month are parties’ last big test of strength ahead of the far right’s bid for national power next year.

• Agent of chaos: The war with Iran is merely the most recent case of the US operating as a destabilising force in global oil markets, writes Emma Ashford.

Graphic of the day

Since the hours after the first US-Israeli strikes on Iran on February 28, a radio station has been broadcasting what appears to be coded orders in Farsi. Former US intelligence officers said the broadcasts were probably an emergency measure enabling Washington to maintain contact with agents within Iran. Listen to the ghostly messages yourself.

Take a break from the news . . . 

Trends spread quickly in South Korea, one of the world’s most densely populated and digitally connected societies. A Dubai chocolate-style chewy cookie known locally as Dujjonku is the latest example, writes Korea correspondent Song Jung-a.