Prime Minister Prayut Chan-o-cha said on Tuesday that he wanted to remain in his position for two more years after the next general election.
Prayut said: "If I am able to remain as the prime minister, I will do so only until 2025."
It was the first time that he spoke about his political future in recent months, with the four-year-long term of his present government ending in March.
Asked for his plans before his tenure as premier ends in 2025, Prayut said: "I will do my best and then find a suitable and acceptable successor."
To the question of whether he would join the new United Thai Nation Party (UTN), Prayut said: "It should have been clear by now."
Asked if he would join the UTN, the prime minister said: "I simply haven't spoken about it. I will speak about it later."
If Prayut stays as the prime minister after the next general election, he can remain in office until 2025 due to the eight-year limit for a prime minister's tenure.
Observers expected him to join the UTN, founded in March last year by a former aide to the prime minister.