The Defender-Europe 2020 manoeuvres, scheduled to run until May, will see 20,000 American soldiers deployed in Europe, along with heavy equipment.
The exercises will include manoeuvres conducted in Poland and the Baltic states.
Poland’s defence ministry said that almost 37,000 soldiers from 18 countries in total would take part in Defender-Europe 2020 and associated exercises.
Poland is contributing over 2,000 troops, heavy equipment and air force units, as well as police officers, border guards and firefighters, state news agency PAP reported.
Polish Defence Minister Mariusz Błaszczak wrote on Twitter: "Together with our allies we are strengthening Poland's security."