I want to know the answer to the following question:
Who was the Prussian ruler who at first  claimed he would help Austria in its battle with France, but later refused to?
All the background I'm provided with is that "Although Archduke Charles warned that the Austrians were not ready for another showdown with Napoleon, a stance that landed him in the so-called "peace party," he did not want to see the army demobilized either.". Is that enough to answer the question?
Answer: no