The US Treasury said it would halt Russia’s ability to make debt payments in dollars through US banks as world leaders sought to punish Moscow for the apparent mass killings of unarmed civilians in Ukraine.

Emmanuel Macron urged a ban on Russian oil and coal imports while Joe Biden called for a war crimes trial following evidence Russian soldiers had committed atrocities in the town of Bucha, north of Kyiv.

“There are very clear indications of war crimes,” Macron said in an interview on France Inter radio on Monday.

Ukraine’s president Volodymyr Zelensky toured Bucha and other suburbs of Kyiv with foreign journalists yesterday as international investigators began to gather evidence of the killings.

The decision by the US Treasury to not permit dollar debt payments to be made from Russian government accounts at US financial institutions will bring Moscow a step closer to a possible default on its obligations to international investors.

“Russia must choose between draining remaining valuable dollar reserves or new revenue coming in, or default,” a US Treasury official said.

More on Ukraine:

• Energy: Berlin has seized Gazprom Germania, the subsidiary of the Russian group operating some of Germany’s largest natural gas storage facilities.

• Oligarch under fire: Alexei Mordashov made his fortune in steel and has interests in coal, gold, travel and media. But after being targeted by EU and UK sanctions, one of Russia’s richest men is fighting to keep his most prized assets.

• Superyachts: Spanish authorities seized a $90mn yacht belonging to Russian oligarch Viktor Vekselberg following a US request. A vessel said to be owned by Roman Abramovich left a Turkish marina after a Financial Times report that the port’s UK-listed operator risked violating sanctions.

• Opinion: Viktor Orban’s election victory in Hungary will be greeted with delight in Moscow, Beijing and Mar-a-Lago — and with dismay in Brussels and Kyiv, writes Gideon Rachman. Vladimir Putin’s catastrophic failure in Ukraine is embarrassing to Xi Jinping, says Jonathan Haslam, emeritus professor in the history of international relations at the University of Cambridge.

Are you from Ukraine? Do you have friends and family in, or from, Ukraine whose lives have been upended? Or perhaps you’re doing something to help those individuals, such as fundraising or housing people in your own homes. We want to hear from you. Tell us via a short survey.

Thanks for reading FirstFT Americas. Here’s the rest of today’s news — Gordon

Five more stories in the news

1. Musk becomes Twitter’s biggest shareholder Twitter shares closed up nearly 30 per cent yesterday after Tesla chief executive Elon Musk disclosed a stake in the social media network worth $2.9bn. The purchase, equivalent to 9.2 per cent of the company’s shares, comes a week after Musk said he was giving the idea of buying a social media company “serious thought”. Alphaville has a explainer, naturally, in tweets.

2. Pandemic windfall The chief executives of Pfizer, BioNTech and Moderna enjoyed a combined pay package of more than $100mn during the pandemic, reflecting the huge success of the vaccines developed by their companies. Albert Bourla of Pfizer, Ugur Sahin of BioNTech and Stéphane Bancel of Moderna also saw their paper wealth grow thanks to share price increases driven by investor enthusiasm.

3. Schultz halts Starbucks buybacks Howard Schultz pledged to suspend Starbucks’ share buyback programme as he began his third term as the US coffee chain’s chief executive. The decision came as Starbucks faces a growing unionisation movement in its home market, rising wage and commodity costs, and potential threats to international growth.

4. UN report on global warming delayed by top polluters Tense negotiations involving the US and China delayed a landmark UN report that concluded that the narrow window to limit global warming would require the phasing out of fossil fuels, an electrified energy system, carbon storage and lower methane emissions.

5. Silicon Valley’s Sequoia Capital names new leader One of Silicon Valley’s oldest and most successful venture capital firms, Sequoia Capital, is changing its leadership. Roelof Botha, a partner at Sequoia who leads its US and European operations, will assume the firm’s leadership in July taking over from billionaire investor Doug Leone, who will retire aged 65.

The day ahead

Ukraine crisis Volodymyr Zelensky will address the UN Security Council after accusing Russian forces of committing war crimes in towns surrounding Kyiv before retreating to concentrate on their campaign in the south and east of the country. Moscow said it would present “empirical evidence” to the meeting proving its forces were not involved.

ISM Services: The Institute for Supply Management’s non-manufacturing index is expected to jump to 58.4 in March from 56.5 in February, according to economists polled by Refinitiv. The ISM Services index fell for a third consecutive month in February as the Omicron-led wave of coronavirus slowed down growth.

Trade: The US trade deficit is forecast to narrow to $88.5bn in February from $89.7bn in January, according to economists polled by Refinitiv. Separately, data from Statistics Canada are expected to show Canada’s trade surplus increased to C$2.9bn in February from C$2.62bn in January, according to a Refinitiv survey.

Federal Reserve speakers Fed Governor Lael Brainard will speak at a Minneapolis Fed conference to discuss how inflation affects workers and families. New York Fed president John Williams will participate in a discussion hosted by The New York Times on “Health and the Economy.”

What else we’re reading

Will Amazon workers’ victory trigger broader change? The number of US employees in a union has halved in the past four decades. But the victory for workers in the Staten Island Amazon warehouse, who last week won the right to form a union, suggests that trend could be changing, argues Sarah O’Connor.

Blockchain-powered broker Sam Bankman-Fried looks more like a student who has just rolled out of bed than the boss of an international cryptocurrency exchange valued at $32bn. But the 30-year-old chief executive of FTX has a futuristic vision for finance based on new protocols being built on blockchains, the distributed ledger technology underpinning cryptocurrencies.

A taipan’s memories For those interested in the inner workings of Hong Kong Inc, as well as a melancholy reminder of how much both the territory and China-US commercial relations have changed for the worse in recent years, the autobiography of former Jardine Matheson and Hutchison Whampoa executive Simon Murray makes fascinating reading.

Why are a leader’s first 100 days so important? Is an action-filled first 100 days a good idea? Not necessarily, say leaders who have been through them. Much depends on the state of the organisation you are taking on. Discover what’s shaking up the world of work with our latest newsletter, Working It, from work & careers editor Isabel Berwick. Sign up here to receive the first edition this week.

The fastest growing companies in the Americas The third annual ranking of the region’s businesses this year — perhaps unsurprisingly — places a US medtech business in the top spot. The full report and analysis will be published on April 28.

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