Which preposition to use with appui

à Occurrences 1%

Quand vint l'heure de la séparation, Lord John dit à Lord D.... tout le plaisir qu'il avait eu à faire sa connaissance, et ajouta: "Maintenant il faut que vous veniez me donner votre appui à la Chambre des communes."

to Occurrences 1%

On Napoleon's return from Elba he voted for him, but made strong objections against the formation of a peerage, which he said was perfectly useless in France, and pregnant with mischief to boot, as it would only serve as an appui to despotism.

Which preposition to use with  appui