US Defence Secretary Jim Mattis told his British counterpart that Washington is concerned that the UK’s military power and diplomatic influence being diminished.
“I am concerned that your ability to continue to provide this critical military foundation for diplomatic success is at risk of erosion, while together we face a world awash with change.”
The letter, leaked to the Sun, was sent on June 12 and will reignite a Whitehall battle over defence funding. Mr Williamson has been pushing for extra cash, stepping up his efforts after the NHS was promised a funding boost.
Mattis also said in the letter:
“A global nation like the UK, with interests and commitments around the world, will require a level of defence spending beyond what we would expect from allies with only regional interests. Absent a vibrant military arm, world peace and stability would be at further risk.”
Highlighting Emmanuel Macron’s recent pledge to pump an extra £260 billion into defence by 2025, Mattis said:
“As global actors, France and the US have concluded that now is the time to significantly increase our investment in defence. Other allies are following suit.”
He stressed that it was “in the best interest of both our nations for the UK to remain the US partner of choice” but “in that spirit, the UK will need to invest and maintain robust military capability”.
In a reference to the Whitehall rows, he added:
“It is not for me to tell you how to prioritise your domestic spending priorities, but I hope the UK will soon be able to share with us a clear, and fully funded, forward defence blueprint that will allow me to plan our own future engagement with you from a position of strength and confidence.”
A Ministry of Defence spokesman said:
“The UK maintains the biggest defence budget in Europe and we have been clear we will continue to exceed Nato’s 2% spending target. The defence secretary launched the modernising defence programme to strengthen our armed forces in the face of intensifying threats.”