Lee, also Singapore's senior minister, made the remarks at the PAP Conference on Sunday, reports Xinhua news agency.
Lee announced that he would continue in the central executive committee in a supporting and advisory role.
Lawrence Wong, who was elected deputy secretary-general in 2022, said the PAP would continue to refresh itself to better meet the needs of a changing society and uphold core values such as honesty, integrity, and incorruptibility.
Noting that he would lead PAP to compete in the next general election, Wong urged the party members to work hard for every vote and win the mandate to govern.
PAP was founded in 1954 and has been the ruling party of Singapore since its independence in 1965.