The first main US forces are expected to arrive in Poland on Saturday to reinforce Nato's eastern flank as the West and Russia wrangle over Russia's military presence near the Ukrainian border.
Defence sources, who requested anonymity due to the sensitive nature of the troops' arrival, told Reuters that the plans could change depending on security and logistics.
US President Joe Biden's administration on Wednesday announced the deployment of about 3,000 American troops to Eastern Europe in the coming days amid a standoff with Russia over Ukraine.
About 1,700 soldiers from the 82nd Airborne Division based at Fort Bragg, North Carolina, are being sent to Poland, Polish Defence Minister Mariusz Blaszczak and the Pentagon said on Wednesday, but only on a temporary basis.
A small group of soldiers from the US Air Force 435th Air Ground Operations Wing, which is headquartered at Ramstein Air Base in Germany, arrived on Thursday to prepare for the arrival of the troops and military equipment.
More flights with equipment landed on Friday at Rzeszow-Jasionka Airport in southern Poland.
The US military already has about 4,500 troops in Poland in both a Nato and a bilateral capacity, mostly stationed in the west of the country on a rotational basis.
