Aljunied GRC MP Chen Show Mao has stepped down as the Workers' Party's (WP) treasurer, just three months after starting a second term in the post he had held since 2014.

He challenged WP chief Low Thia Khiang for the post of secretary-general at the Central Executive Council (CEC) election in May and lost, but was persuaded to continue as treasurer. Sources said he reluctantly agreed to remain but would have preferred to hand over, given his unsuccessful bid for the top WP post.

Mr Low confirmed that Mr Chen had resigned as treasurer when contacted by The Straits Times. Mr Chen, who quit at a CEC meeting on Tuesday, is still a council member.

Deputy treasurer and Non-Constituency MP Dennis Tan has succeeded Mr Chen, and former Punggol East MP Lee Li Lian, a council member, is now deputy treasurer.

Mr Low, citing party confidentiality, declined to reveal what transpired at Tuesday's CEC meeting when he was asked about Mr Chen's reasons for stepping down as treasurer and whether CEC members tried to persuade him to stay.

"I am only sticking with the facts that Mr Chen is no longer treasurer. As for his reasons for stepping down, it's more appropriate that you ask him," he said on Wednesday after his Meet-the-People Session in Hougang Avenue 6.

When contacted yesterday, Mr Chen declined to elaborate on his decision, saying simply that "I have little comment to add on the subject".

A party insider close to Mr Chen downplayed the incident, saying the resignation had nothing to do with his leadership challenge.

Mr Low, who had never faced a contest since becoming secretary- general in 2001, retained the post in May with 61 votes to Mr Chen's 45.

The source said Mr Chen indicated after his loss that he did not want a second term as treasurer. But the CEC wanted him to stay on.

Mr Chen agreed so as to ensure a smooth handover to a successor, and to dampen speculation of an internal split so soon after his leadership challenge, the source said.

Mr Tan, the new treasurer, did not comment on Mr Chen's stepping down, but said he was willing to step up and assume the position as he had served as deputy.