Poland will purchase 250 US tanks in a $6 billion agreement, according to the Defense Minister, as the NATO member strives to strengthen its defenses.

Since Russia annexed Crimea from Ukraine in 2014, Poland, like many other eastern European countries, has been alarmed by what it perceives as rising Russian assertiveness.

“Of course, this is a response to the international security concerns we confront,” Mariusz Blaszczak said during a press briefing.

“Our mission is to keep a possible aggressor at bay. We’re all aware of the aggressor’s location.”

Blaszczak said Poland would spend 23.3 billion zlotys ($6.00 billion) on the Abrams tanks and an accompanying logistical and training package, as well as on upgrading infrastructure and buying ammunition.

In May, Poland announced that it would buy 24 armed drones from Turkey, becoming the first NATO member to buy Turkish-made unmanned aerial vehicles (UAVs).