WASHINGTON, Oct 3 (AFP) - The Biden administration's next security assistance package for Ukraine is expected to include four High Mobility Artillery Rocket System (HIMARS) launchers, munitions, mines and mine-resistant vehicles, two sources briefed on the US$625 million package told Reuters on Monday (Oct 3).

The package, expected to be announced as soon as Tuesday, is the first aid package since Russia's most recent declared annexation of Ukrainian territory and the second Presidential Drawdown Authority (PDA) since Ukraine made large battlefield gains in mid-September.

Russia's declared annexations followed what it called referendums in occupied areas of Ukraine. Western governments and Kyiv said the votes breached international law and were coercive and non-representative.

By using drawdown authority, the four HIMARS launchers and associated rockets, some 200 Mine-Resistant Ambush Protected (MRAP) vehicles, ammunition for Howitzers and mines, can be sent to Ukraine in the coming days.

Presidential Drawdown Authority allows the US to transfer articles and services from stocks quickly without congressional approval in response to an emergency.

This is the first package of the US government's 2023 fiscal year which is currently functioning under a stop gap-funding measure and allows President Joe Biden to drawdown up to US$3.7 billion in surplus weapons for transfer to Ukraine through mid-December.

Last week, the United States unveiled a US$1.1 billion arms package for Ukraine which included 18 High Mobility Artillery Rocket System (HIMARS) launcher systems, accompanying munitions, various types of counter drone systems and radar systems.

But last week's aid package was funded by the Ukraine Security Assistance Initiative (USAI) meaning the government has to procure the weapons from industry, rather than pulling them from existing US weapons stocks.

Made by Lockheed Martin Corp the HIMARS launchers' accuracy and longer range have allowed Kyiv to reduce Russia's artillery advantage.

The US has thus far pledged 16 HIMARS launchers to Ukraine using PDA.

The White House declined to comment on the package.

The officials, speaking on the condition of anonymity, said that the weapons package can change in value and content until the last minute.

This announcement would mark more than US$16.8 billion worth of US security assistance since Russia invaded Ukraine on Feb 24.