Tensions over Ukraine escalated further after Russian President Vladimir Putin put his nuclear forces on increased alert.
The U.S. and some European countries said they were dramatically upping their deliveries of weapons to Ukraine, including more Stinger missiles and fighter jets.
Ukrainian President Volodymyr Zelenskyy’s office, meanwhile, announced plans for a meeting Monday with a Russian delegation at an unspecified location on the Belarusian border.
Russia’s military assault on Ukraine entered its fifth day with fighting in the streets of the country’s second-largest city, Kharkiv, and troops moving closer to the capital, Kyiv.
Here are the things to know about the Russian invasion of Ukraine and the security crisis in Europe:
Unearthing long-buried fears from the Cold War, Putin on Sunday ordered Russian nuclear weapons prepared for increased readiness to launch.