Karácsony announced entering the primary race on Facebook, saying that he accepted the nomination of opposition party Párbeszéd, because he feels that Hungary is "in trouble".

"Perhaps the greatest of many problems is that we feel less and less that Hungary is our common homeland, that Hungary is one and indivisible; we feel more and more that our homeland is divided to the extreme," he said.

Karácsony added that he wants to work for the Hungarians who are constantly struggling, noting that he does not want to fight for the privileged 1%, "But for the 99% who live in different ways, sympathize with different parties, and live from one day to the next".

In addition to Karácsony, Péter Jakab (Jobbik), Klára Dobrev (DK), András Fekete-Győr (Momentum) and Péter Márki-Zay (Mindenki Magyarországa Mozgalom) are also in the race to become the opposition's joint candidate for PM. The candidate will be selected in two rounds, with the three candidates who receive the most votes going through to the second round.

The first round to elect Orbán's challenger will be held between September 18-26, and the second round will take place between October 4-10.