As Russia's war on Ukraine drags on, U.S. security assistance is shifting to a longer-term campaign that will likely keep more American military troops in Europe into the future, including imminent plans to announce an additional roughly $3 billion in aid to train and equip Ukrainian forces to fight for years to come, U.S. officials said.

U.S. officials told The Associated Press that the package is expected to be announced Wednesday, the day the war hits the six-month mark and Ukraine celebrates its independence day. The money will fund contracts for drones, weapons and other equipment that may not see the battlefront for a year or two, they said.

The total of the aid package — which is being provided under the Ukraine Security Assistance Initiative — could change overnight, but not likely by much. Several officials spoke on condition of anonymity to discuss the aid before its public release.

Unlike most previous packages, the new funding is largely aimed at helping Ukraine secure its medium- to long-term defense posture, according to officials familiar with the matter. Earlier shipments, most of them done under Presidential Drawdown Authority, have focused on Ukraine’s more immediate needs for weapons and ammunition and involved materiel that the Pentagon already has in stock that can be shipped in short order.

In addition to providing longer-term assistance that Ukraine can use for potential future defense needs, the new package is intended to reassure Ukrainian officials that the United States intends to keep up its support, regardless of the day-to-day back and forth of the conflict, the officials said.

NATO Secretary-General Jens Stoltenberg noted the more extended focus Tuesday as he reaffirmed the alliance’s support for the conflict-torn country.

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“Winter is coming, and it will be hard, and what we see now is a grinding war of attrition. This is a battle of wills, and a battle of logistics. Therefore we must sustain our support for Ukraine for the long term, so that Ukraine prevails as a sovereign, independent nation,” Stoltenberg said, speaking at a virtual conference about Crimea, organized by Ukraine.

Six months after Russia invaded, the war has slowed to a grind, as both sides trade combat strikes and small advances in the east and south. Both sides have seen thousands of troops killed and injured, as Russia’s bombardment of cities has killed countless innocent civilians.

There are fears that Russia will intensify attacks on civilian infrastructure and government facilities in Ukraine in the coming days because of the independence holiday and the six-month anniversary of the invasion.

Late Monday, the U.S. Embassy in Ukraine and the State Department issued a new security alert for Ukraine that repeated a call for Americans in the country to leave due to the danger.

“Given Russia’s track record in Ukraine, we are concerned about the continued threat that Russian strikes pose to civilians and civilian infrastructure,” it said.

To date, the U.S. has provided about $10.6 billion in military aid to Ukraine since the beginning of the Biden administration, including 19 packages of weapons taken directly from Defense Department stocks since August 2021.

U.S. defense leaders are also eyeing plans that will expand training for Ukrainian troops outside their country, and for militaries on Europe’s eastern and southern flanks that feel most threatened by Russia’s aggression.