The Trump administration's first U.S. weapons aid packages for Ukraine have been approved and could soon ship as Washington resumes sending arms to Kyiv - this time under a new financial agreement with allies - two sources familiar with the situation told Reuters.

This is the first use of a new mechanism developed by the U.S. and allies to supply Ukraine with weapons from U.S. stocks using funds from NATO countries.

Undersecretary of Defense for Policy Elbridge Colby has approved as many as two $500 million shipments under the new mechanism called the Prioritized Ukraine Requirements List, known under the acronym PURL, the sources said.

The renewed transatlantic cooperation, which aims to bolster Kyiv with as much as $10 billion worth of weapons, comes as U.S. President Donald Trump has expressed frustration with Moscow's ongoing attacks on its neighbour despite his efforts to achieve a negotiated end to the conflict.

So far, the Trump administration has only sold weapons to Ukraine or shipped donations which were authorised by former President Joe Biden, who was a staunch supporter of Kyiv.

The sources declined to give an exact inventory of what has been approved for purchase by the Europeans for Ukraine, but said it included air defence systems, which Ukraine says it needs urgently given the huge increase in Russian drone and missile attacks.

One of the sources said the PURL list was making its way through the process after clearing the Pentagon's policy unit.

The Pentagon did not immediately respond to a request for comment.

"It's the stuff they've been asking for. A lot of stuff," said the source. "It's the flow that's allowed them to stabilise the lines thus far."

According to experts, Ukraine's needs remain consistent with previous months - air defences, interceptors, systems, rockets, and artillery.

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