FILE PHOTO: Hungarian Prime Minister Viktor Orban sits before addressing parliament in Budapest, Hungary, May 18, 2018. REUTERS/Bernadett Szabo

BUDAPEST (Reuters) - Hungary’s government will begin a major revision of the country’s constitution in the autumn that could take 12-18 months, Prime Minister Viktor Orban told state radio on Friday.

Right-wing nationalist Orban, who was reelected with a landslide in April elections for a third straight term, did not reveal any further details.

He said “discussion” about changes to the 2011 constitution would start in September.

Orban’s ruling Fidesz party holds 133 of 199 seats in Hungary’s parliament which ensures the necessary two-third majority to change any laws.

“In the autumn we would like to launch a 1-1.5 year long constitution revision where we will look at what has worked and what could have worked ... and find potential gaps which we need to fill in with new constitutional text,” Orban said.

After he rose to power in 2010, Orban used his strong mandate in parliament to rewrite Hungary’s constitution.

One of the criticized changes was curbing the powers of the top court in budget and tax matters.