He was previously a civil servant, including being the Secretary to the Government.
[1] He was elected to parliament to represent Nukufetau in a by-election held on 30 June 2023.
[2][3] In August 2023, Nelesoni was appointed as the Minister for Justice, Communications, and Foreign Affairs.
[2][4] to succeed Simon Kofe, who resigned as the minister to focus on parliamentary work to amend the Constitution.
[5] During Nelesoni's term as foreign minister, prime minister Kausea Natano signed the Australia–Tuvalu Falepili Union, a bilateral treaty which covered migration, climate change, security arrangements and their bilateral diplomatic relationship.