His Excellency is wearing the order of Saint Gregory the Great (Knight Commander's cross with Star)
Looks like he's a Knight Grand Cross of the Order of Pius IX (the Blue & Red ribband plus the star), a Knight Commander of the Order of St. Gregory the Great (the neck order on yellow and red ribbon), and a member of the Sovereign Military Order of Malta (the miniature medal on a black ribbon).
He is also wearing the Order of Pius IX with the rank of Knight Grand Cross. This knighthood is often given to diplomats accredited to the Holy See. It ranks above the Order of St Gregory in precedence.