It was inevitable, perhaps: the UK and Italy - the only Eurofighter Typhoon partners that also plan to buy the F-35 Joint Strike Fighter - are being forced to choose between the two aircraft, according to a report in The Times.
The Times says the UK Ministry of Defence is trying to find a way out of its committment to buy 88 more Tranche 3 Typhoons, and to reduce, delay or cancel the final order. Italy also wants to cut its Tranche 3 order, the report suggests.
Citing defence sources, The Times says the UK Treasury will not allow the MoD to buy both Tranche 3 Eurofighters and the 150 or so Lockheed Martin F-35Bs it wants. BAE Systems has a piece of both fighter programmes.
My first guess is the JSF will win - the F-35B is the only STOVL option to replace the UK's Harriers on land and at sea. The Royal Navy's new CVF carriers could operate conventional fighters, but are being designed around the JSF.
And because of delays in developing the Eurofighter's multi-role capability, the F-35 will enter service around 2014 with a greater combat potential.
But - and it is a big but - cancelling Tranche 3 Typhoons would leave the UK (and Italy) entirely at the mercy of the US budget process, which is capable of cutting, delaying and even cancelling the JSF programme without consideration of its allies.