President Joe Biden signed an executive order Thursday that will allow the Pentagon to tap into reserve forces for deployment to Europe as part of its long-standing NATO mission on the continent.
According to a copy of the order released by the White House, it allows the military to use up to 3,000 reserve service members to augment its forces in Europe, which grew in reaction to Russia's invasion of Ukraine.
The Pentagon said last year it increased the troop presence on the continent by about 20,000 troops as Russian President Vladimir Putin attempted to seize the country, bringing the total U.S. force in Europe to more than 100,000.
"It's unlocking additional forces for use in support of this operation," the Pentagon's top spokesman, Brig. Gen. Pat Ryder, told reporters on a phone call Thursday.
Lt. Gen. Douglas Sims, the Joint Staff director for operations who also briefed reporters, said, "These authorities will enable the department to better support and sustain its enhanced presence and level of operations" in Europe.
Sims stressed that "these are not additional forces."
"Over time, where we may have had someone from an active component organization doing something, that job now, under these authorities, may be something that a reserve component unit may be able to do," he said.
The mission -- officially dubbed "Atlantic Resolve" -- goes back to 2014 when the U.S. was trying to bolster the NATO alliance and deter Russia's aggression in Ukraine's Donbas region. That year, Putin ordered the invasion and annexation of Ukraine's Crimea, triggering international condemnation.
Since Russia invaded Ukraine in 2022, the mission has gained increased relevance and attention -- and the U.S. has contributed more than $40 billion in security assistance, as well as training for Ukrainian troops.
Sims noted that the mission will be considered a "contingency operation," which "benefits troops and families with increases in authorities, entitlements, and access to the reserve component forces and personnel."
The designation means more "personnel-related entitlements that ... give activated reservists the same benefits as active component personnel," as well as a way for the Pentagon to better track spending directly associated with the mission, Ryder said.
The units that will be providing the service members have yet to be identified.
"It will really depend on what's required from the commander," Sims said. As a result, it is unclear whether the move will mean a deployment of new or different military equipment.