Teri Schultz

For the first time, NATO allowed journalists to witness its annual nuclear exercise, a once-secret event that now serves as both a show of transparency and a message of deterrence toward Russia.

Ukrainian President Volodymyr Zelenskyy meets with European Union leaders Thursday as they prepare massive new financing for Kyiv's war effort.

Many Danes are rethinking their personal security, and stocking up on emergency supplies, amid unidentified drone appearances. Denmark's leaders warn that Russia is waging a "hybrid war."

After a week of flights by unidentified drones, the U.S. and other NATO countries sent troops and equipment to Denmark to protect its capital during meetings with European Union leaders Wednesday.

Drones were spotted over four of Denmark's civilian and military airports in the second mystery sighting this week. European Union defense ministers will hold a virtual meeting Friday to discuss this.

Drones were spotted over four of Denmark's civilian and military airports in the second mystery sighting this week. European Union defense ministers will hold a virtual meeting Friday to discuss this.

NATO countries are warning Russia that they will retaliate -- in unspecified ways -- if the country continues to fly military aircraft in their airspace.

Russian fighter jets illegally entered Estonian airspace Friday. A senior Estonian official says it's time for NATO forces to consider shooting down the next Russian plane that crosses the line.

Russian fighter jets illegally entered Estonian airspace Friday. A senior Estonian official says it's time for NATO forces to consider shooting down the next Russian plane that crosses the line.

A plane carrying European Commission President Ursula von der Leyen was temporarily blocked from landing in Bulgaria due to what Bulgarian authorities say was Russian GPS jamming.