The wily tactician left some wriggle room: his renunciation was to facilitate a grand alliance of the right; if it does not happen, he could make another U-turn.
The venerable Kingdom of Prussia and the Austrian Empire made a powerful alliance, while the United Kingdom and France were locked in an economic stalemate.
And there's a very substantial group who are anti-Austrian, who think that Austria have somehow tricked France into this alliance, and that Austria is getting a better deal out of the alliance than France is.
Three of them, Austria, Prussia, and Russia, under the leadership of the Czar, Alexander I, in the autumn of 1815, had entered into a Holy Alliance to sustain by reciprocal service the autocratic principle in government.