It’s unmistakable to me now; the shape of a Treecreeper against a tree. That pose, the stiff tail to balance it, the curved beak; it can’t be anything other than a Treecreeper.
Hold on though, I’m in the south of Italy. That means it can’t be a Treecreeper Certhia familiaris. It must be a Short-Toed Treecreeper Certhia brachydactyla instead.
It’s good that I know that just from where in the world it is, because I really can’t see just how long its toes are.