Seoul, Apr 15 (IANS): South Korean authorities on Saturday began the official registration of candidates contesting the upcoming presidential election.

After the two-day registration, the official campaign period for the May 9 election will begin on Monday, according to the National Election Commission (NEC).

A total of 26 potential candidates had registered with the NEC after preliminary registrations began on March 10, when former President Park Geun-hye was forced out of office by a Constitutional Court ruling, prompting the rare presidential by-election, Yonhap News Agency reported.

As of Friday, 21 remained on the list after the rest withdrew their preliminary, mostly self-imposed candidacies, the NEC said.

Currently, only two presidential hopefuls are seen able to garner support: Moon Jae-in of the liberal Democratic Party of Korea and Ahn Cheol-soo of the centre-left People's Party.

Both enjoyed an approval rating of over 30 per cent each in polls on the upcoming election.