The US sealed a defence cooperation deal with Polish officials that will pave the way for the redeployment of American troops from Germany to Poland.
"This is going to be an extended guarantee: a guarantee that in case of a threat our soldiers are going to stand arm-in-arm," Poland's President Andrzej Duda said during the signing ceremony.
“It will also serve to increase the security of other countries in our part of Europe,” Duda said.
US Secretary of State Mike Pompeo is in Warsaw after visiting four nations in central and eastern Europe.
The US and Poland have "proudly executed" this defence agreement and it "paves the way" for an additional 1,000 troops on top of the 4,500 already present, Pompeo said at a later press conference.
Pompeo called the deal "an important strategic move" for the United States.
"The presence of American troops in Poland enhances our deterrence potential because we are closer to the potential source of conflict," said Polish foreign minister Jacek Czaputowicz. He added that the presence of US troops in Poland was important to Polish security.
The new deal comes after the US announced plans to pull nearly 12,000 soldiers out of Germany. About 5,400 troops will be deployed elsewhere in Europe including in Poland. Some 6,400 will return home.
US President Donald Trump has long complained that Germany does not spend the NATO target of 2% of its GDP on defence and that it was taking "advantage" of the US.
The US European Command was first created in 1952 and at the height of the Cold War there were more than 400,000 US troops stationed in Europe.
The collapse of the Soviet Union led to a gradual withdrawal of American troops.
Pompeo also visited the Tomb of the Unknown Soldier with Polish officials to mark the centennial of Poland’s landmark victory against the Russian Bolsheviks in 1920 during the Polish-Soviet war.