New Delhi, April 28 -- Outgoing Hungarian Prime Minister Viktor Orban will not take his seat in parliament following a landslide election loss this month, and will instead focus on rebuilding his nationalist-populist political community, he announced Saturday in a video on social media.

Hungary's April 12 election brought an end to Orban's 16 years in power when voters cast their ballots overwhelmingly for a center-right challenger who promised to crack down on endemic corruption and restore Hungary's democratic institutions that had been eroded under Orban.

That challenger, the Tisza party led by Hungary's incoming Prime Minister Peter Magyar, won a two-thirds majority in parliament that will allow it to undo many of Orban's policies....