Prime Minister Shinzo Abe suggested Thursday he has no intention of serving another four-year term as president of the ruling Liberal Democratic Party when his third term expires in September 2021.

Abe's remarks came after some LDP heavyweights hinted at the possibility of changing a party rule to make it possible for him to remain in the post beyond the current limit of three terms.

"Seeking a fourth term is prohibited by a party regulation. It is a matter of course to abide by the rule," Abe, who returned to power in late 2012, told a Diet committee session.

"As this is my last tenure, I will concentrate on achieving results with full might," said the 64-year-old, who is set to become Japan's longest-serving prime minister in November this year, surpassing Taro Katsura's record of 2,886 days in office.

Earlier this week, LDP Secretary-General Toshihiro Nikai said a fourth term for Abe as head of the party was "fully possible."

"There is no problem when it is hard to find someone else to replace him," Nikai, the LDP's No. 2, said at a news conference on Tuesday.

Katsunobu Kato, chairman of the party's decision-making general council and a close aide to Abe, has also mentioned the possibility of the prime minister serving a fourth term.

In 2017, the LDP changed its term limit for party leaders in a move that was initiated by Nikai, extending the cap to three consecutive three-year terms from the previous limit of two consecutive three-year terms.