In a July 31st note to the British ambassador in Paris, British foreign secretary Sir Edward Grey explains London’s position on the eve of war, resisting calls that Britain back France and Russia:

Sir,

M. Cambon [France’s ambassador to Germany] referred today to a telegram, saying that our uncertainty about intervention was the encouraging element in Berlin, and that if we would only declare definitely on the side of Russia and France, it would decide the German attitude in favor of peace.

I said that it was quite wrong to suppose that we had left Germany under the impression that we would not intervene. I have refused overtures to promise that we should remain neutral. I not only declined to say that we would remain neutral; I had even gone so far as to say to the German Ambassador that, if France and Germany became involved in war, we should be drawn into it.

I said that we had come to the conclusion, in the Cabinet today, that at the present time we could not give any pledge… we should have to put our policy before Parliament, we could not pledge Parliament in advance. Up to the present moment, we did not feel that any treaties or obligations of this country were involved. Further developments might alter this situation and cause the Government and Parliament to take the view that intervention was justified. The preservation of the neutrality of Belgium might be … an important factor in determining our attitude.

The latest news was that Russia had ordered a complete mobilisation of her fleet and army. This, it seemed to me, would precipitate a crisis, and would make it appear that German mobilisation was being forced by Russia.

It could not be to England’s interest that France should be crushed by Germany. We should then be in a very diminished position with regard to Germany. In 1870, we had made a great mistake in allowing an enormous increase in German strength; and we should now be repeating the mistake.

I said that the Cabinet would certainly be summoned as soon as there was some new development, but at the present moment the only answer I could give was that we could not undertake any definite engagement.