The Air Defender 23 exercise starting next week will see 10,000 participants and 250 aircraft from 25 nations respond to a simulated attack on a NATO member country.
The United States alone is sending 2000 US Air National Guard personnel and about 100 aircraft to take part in the training manoeuvres.
"This is an exercise that would be absolutely impressive to anybody who's watching, and we don't make anybody watch it," US Ambassador to Germany Amy Gutmann said.
"It will demonstrate beyond a shadow of a doubt the agility and the swiftness of our allied force in NATO as a first responder," she said.
"I would be pretty surprised if any world leader was not taking note of what this shows in terms of the spirit of this alliance, which means the strength of this alliance," Gutmann said.
"And that includes Mr Putin," she added, referring to Russian President Vladimir Putin.
While the drill, which is being led by Germany, has been planned since 2018, Russia's invasion of Ukraine last year has jolted NATO into preparing in earnest for the possibility of an attack on its territory.
Sweden, which is hoping to join the alliance, and Japan are also taking part in the exercise.
