He secured a seat from Fidesz National List in the 2002 Hungarian parliamentary election.

Illés was appointed Secretary of State for Environmental Protection and Water in the Ministry of Rural Development on 2 June 2010.

[2] In September 2013, Illés responded to a formal question from Bernadett Szél (LMP) about the Roșia Montană Project in Romania, where amongst other things he said "just because you’re pretty doesn’t also mean you’re smart," and lectured her for daring to utter the Prime Minister Viktor Orbán's name.

"[4] As environmentalist, he strongly criticized the planned upgrade of the Paks Nuclear Power Plant, signed between the Hungarian and Russian governments in January 2014.

[5] Since then, Illés accused Orbán's government in several cases with corruption and development of oligarchic system.