Sanae Takaichi, president of Japan's ruling Liberal Democratic Party (LDP), was elected as the country's 105th prime minister on Wednesday by lawmakers in parliament.

At a special Diet session convened on the day, the lower house and the upper house held a prime ministerial appointment vote, respectively.

In the House of Representatives vote, Takaichi secured 354 votes in the first round, defeating head of the main opposition Centrist Reform Alliance (CRA) Junya Ogawa with 50 votes and other rival candidates.

The House of Councillors headed to a runoff vote after no candidate secured a majority in the first round. Takaichi then led with 125 votes, followed by Ogawa with 65.

The powerful lower house also elected Eisuke Mori, a veteran LDP lawmaker and former justice minister, as its speaker and Keiichi Ishii, a member of the CRA, as vice speaker.

Takaichi and her cabinet resigned en masse earlier in the morning, as required by the constitution, before the launch of her new cabinet later in the day.

With Takaichi's cabinet appointed just months ago after she became LDP leader and subsequently prime minister in October, changes to the lineup are unlikely, local media said.

Along with LDP executives, all the ministers, including Foreign Minister Toshimitsu Motegi, Finance Minister Satsuki Katayama and Defense Minister Shinjiro Koizumi, are expected to retain the posts they held in Takaichi's first cabinet, Kyodo News reported.