It was a prophetic pronouncement. But Clemenceau gave in. In return for abandoning the Rhine he accepted solemn guarantees of his country's frontier from his two great allies. Neither ally kept its word. Both houses of the British parliament approved the Treaty of Guarantee in July 1919, but on the condition that the United States also ratify it. The U. S. Senate refused to approve either it or the Versailles Treaty, and the British assent was nullified.