The Pentagon will send Ukraine an additional $725 million in military assistance from its stockpiles, including anti-personnel land mines, drones, portable antiaircraft missiles and anti-tank missiles.

In a statement, the Pentagon said on Monday that the shipment was part of a surge in security aid as Ukraine battles a renewed Russian offensive.

The new support comes amid deep concerns in Ukraine that the incoming Trump administration might cut off military aid to the country. President-elect Donald J. Trump has vowed to end the war quickly, though he has not said how. But Vice President-elect JD Vance has outlined a plan that would allow Russia to keep the Ukrainian territory it has seized.

The new tranche will be the single largest that the United States has sent to Ukraine since a $1 billion shipment was announced April 24, just days after the House approved new aid to the country after a monthslong hold.

The arms are provided under what is called presidential “drawdown” authority, which allows the administration to transfer Pentagon stocks to Ukraine instead of waiting the months or years it can take for defense contractors to manufacture weapons under new contracts.

There had been 15 such drawdowns totaling $4.6 billion of arms, ammunition, vehicles and other supplies since the $1 billion package was announced.

Thank you for your patience while we verify access. If you are in Reader mode please exit and log into your Times account, or subscribe for all of The Times.

Thank you for your patience while we verify access.

Already a subscriber? Log in.

Want all of The Times? Subscribe.