Semisi Kioa Lafu Sika is a Tongan politician, businessman, and Member of the Tongan Parliament from 2010 to 2021. He served as acting prime minister in September 2019, following the death of ʻAkilisi Pōhiva. He is currently leader of the Democratic Party of the Friendly Islands.

The prime minister of Tonga is the country's head of government. Tonga is a monarchy with the king, currently Tupou VI, former prime minister, as head of state. The current prime minister is Siaosi Sovaleni, who was elected on 15 December 2021 and appointed on 27 December 2021. Sovaleni was elected with 16 votes.