The Pentagon has said Poland’s offer to give all of its MIG-29 fighter jets to the US so they can be passed to Ukraine is not “tenable”.

Spokesman John Kirby said the proposal to deliver the planes to the US Ramstein air base in Germany “raises serious concerns for the NATO alliance”.

“It is simply not clear to us there is a substantive rationale for it,” he said.

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Key developments:
• US bans Russian energy imports and UK will stop using Russian oil this year
• Zelenskyy echoes Churchill in appeal to UK and vows to ‘fight to the end’ against Russia
• Poland offers all its MIG-29 fighter jets to US in plan to provide aircraft to Kyiv
• Ukraine’s first lady writes open letter condemning Putin
• Ukraine claims senior Russian general has been killed in fighting near Kharkiv
• Russia has warned it could cut its gas supplies to the West through the Nord Stream 1 pipeline

The plan would help Ukrainians by providing them with more aircraft but also raises the risk of the war expanding beyond Ukraine.

‘Not tenable’

Mr Kirby said the US is worried about the prospect of warplanes departing from a US and NATO base to fly into airspace contested with Russia.

Russia has said that supporting Ukraine in this way would mean that NATO was now participating in the war, and has warned of potential retaliation.

“We will continue to consult with Poland and our other NATO allies about this issue and the difficult logistical challenges it presents, but we do not believe Poland’s proposal is a tenable one,” Mr Kirby said.

A US official said the Pentagon and State Department were not consulted by Poland before the surprise announcement it was ready to hand over its entire fleet of the jets “immediately and free of charge” and put them “at the disposal of the US government”.

“There was no co-ordination for the jets to ever cross into US custody,” they said, speaking anonymously.

Poland won’t give planes directly to Ukraine

Poland had suggested it would hand over its Soviet-era fighters and in turn receive American F-16s to make up for their loss.

“The US position was in support of Poland sending the jets directly to Ukraine, not for the US to act as an intermediary,” the official added.

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Polish Prime Minister Mateusz Morawiecki said his country is “not ready to make any moves on our own” because “we are not party to this war”.

“Any decision of delivering offensive weapons has to be taken by the entire NATO on a unanimous basis,” he added.

Over the weekend, Ukrainian President Volodymyr Zelenskyy made a “desperate plea” to US Congress members for further military aid that is not currently being supplied by the West, including planes.

Ukraine’s military pilots are not trained to fly US fighter jets and would be far more equipped to handle Soviet-era aircraft.