Why Biden approved F-16 transfers to Ukraine
Why are F-16 jets so important?
It was the Dutch premier, Mark Rutte - supported by the British prime minister Rishi Sunak - who appears to have persuaded Washington to permit the transfer of F-16 fighter jets to Ukraine.
Rutte wrote to the US president Joe Biden a few days ago formally requesting permission to lend Ukraine the Lockheed Martin jets. Britain backed the initiative, in private and in public, but was not in a position to make the request because the UK does not own F-16s.
Only a few days ago, Sunak and Rutte announced they were building an "international coalition" to "provide Ukraine with combat air capabilities, supporting everything from training to procuring F-16s". Denmark and Belgium are also part of this coalition.
President Biden's announcement yesterday means NATO countries can start to train Ukraine pilots to fly what are regarded as the great workhorses of military aircraft - which have been in use since the late 1970s.
The UK can and will provide preliminary training for Ukrainian pilots. This will start within weeks.
However, the jets themselves will not be transferred for months. They are likely to come from the Netherlands and Poland in the first instance.
According to government sources, it is possible that at some point in the future, the UK will provide Ukraine with some of the Typhoon aircraft owned and operated by the RAF.
The announcement of this significant enhancement to Ukraine's air capability, during the G7 summit here in Japan, is meant to be a message to Vladimir Putin and Russia that the West and other democratic nations are not wavering in their support for Ukraine.
However intelligence sources tell me they expect the conflict between Ukraine and Russia to endure for several gruelling years. Ukraine's soon-to-be-launched summer offensive against Russia's troops may well reclaim significant territory, but there is no expectation that Russia can be driven from the country altogether.
In an interview with me yesterday, Sunak said: "Russia needs to know that we're not going away. They can't out last us in this conflict. We will continue to defend Ukraine".
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