The U.S. Army in Europe will have a permanent footprint of three fully manned brigades on the continent by next February, defense officials announced Wednesday.

The Army will begin continuous rotations of U.S.-based armored brigade combat teams on nine-month deployments to train with Eastern European allies, officials said.

The armored brigades will deploy from the U.S. with their own gear, officials said. They will add to the current force of two combat brigades permanently stationed in Europe.

The move is part of the European Reassurance Initiative that the Pentagon unveiled in February and marks an increase from the current force of two brigades and more limited rotational presence.

It's part of the Pentagon's ongoing response to Russia's increasingly aggressive military activity along NATO's eastern border.

"This is a big step in enhancing the Army's rotational presence and increasing their combat equipment in Europe," Gen. Philip Breedlove, the EUCOM commander, said in a statement along with the announcement.

"This means our allies and partners will see more capability — they will see a more frequent presence of an armored brigade with more modernized equipment in their countries," Breedlove said.

For the past year, the Army has deployed some rotational units into Eastern Europe and used a set of pre-positioned gear known as the European Activity Set, which includes vehicles, weapons, communication equipment and other essential supplies to outfit a combat brigade.

In February 2017 when the Army begins rotations of fully equipped brigades, that European Activity Set gear will remain in Europe and will be repaired and upgraded to provide for additional combat capability in the event of an emergency. That equipment would allow for the rapid deployment of ground forces.

By the end of 2017, the Army plans to have a continuous presence of three fully equipped army brigade combat teams, one Armored, one Airborne, one Stryker as well as one pre-positioned set of combat-ready equipment sufficient to support another armored brigade combat team.

The Pentagon's latest budget request includes $3.5 billion for Eastern Europe to allow for a permanent presence of American troops forward-deployed closer to the Russian border in countries such as Poland, the Baltics and Romania. The "rotational" troops at locally owned military installations will swap out "heel to toe," meaning there will be no permanent garrison of U.S. forces like those in Germany and Italy but troops would retain a constant presence on the ground in the East.