The former Barcelona head coach will take over from current Allianz Arena incumbent Jupp Heyckes at the end of the season on a three-year deal.
DFL's chief executive Rettig believes that international football fans will pay more attention to the BuLi now that a famous face like Guardiola is set to coach in Germany.
He said to Bild: "I congratulate Bayern at signing Pep Guardiola. This once again shows the great international significance of the German football league.
"Guardiola means the international interest in the Bundesliga will surely rise."
Hannover president Kind also congratulated his league rival, and believes that the club has shown its financial muscle by securing the 41-year-old coach's commitment to add to the signing of Javi Martinez for 40 million euros last summer.
He told Sky Sports News: "Bayern Munich have already shown with the transfer of Martinez that they clearly demonstrate they are strong financially and in the sporting department.
"Bayern want to be number one in Germany, and they want the league to grow internationally successful."