The World in Brief from The Economist

America’s Treasury department said it would begin to buy back up to $6bn worth of long-dated government debt on Thursday as it attempts to contain borrowing costs.

America’s Treasury department said it would begin to buy back up to $6bn worth of long-dated government debt on Thursday as it attempts to contain borrowing costs; Brent crude, the international oil benchmark, surpassed $100 a barrel for the first time since July, as traders reacted to strikes between America and Iran.

Brent crude, the international oil benchmark, surpassed $100 a barrel for the first time since July. Also, OpenAI said it used an unreleased artificial-intelligence model to crack one of the trickiest problems in mathematics.

OpenAI said it used an unreleased artificial intelligence model to crack one of mathematics’ trickiest problems.

OpenAI said it used an unreleased artificial intelligence model to crack one of mathematics’ trickiest problems; America carried out strikes around Kharg Island, Iran’s crucial oil-export terminal, according to Iranian media.

The Houthis, an Iran-backed Yemeni rebel group, attacked four cities in southern Saudi Arabia, setting fire to some energy facilities and wounding at least 73 people. Also, Canada imposed retaliatory tariffs on around 700 American products, including steel, dairy and home appliances.

Canada was set to impose new tariffs on around 700 American products, including steel, dairy and home appliances.

Canada was set to impose new tariffs on around 700 American products, including steel, dairy and home appliances; Iran promised to retaliate against American attacks, warning that energy companies have assets that remain “sprawling, accessible and exposed” in the region