The lawyer of former SCDF chief Peter Lim on Monday morning said his client categorically denies any allegations of corruption, and will disprove the "nebulous" arguments of the prosecution.

Lawyer Hamidul Haq said that Lim had a "genuine friendship" with Ms Pang Chor Mui of Nimrod Engineering, and it "involved playful and teasing banter, and intimacy between them".

The oral sex was a "one-off encounter" and was merely a physical expression of the personal relationship shared between the two, he said. Lim did not at anytime request to be fellated by Ms Pang.

The lawyer noted that Ms Pang - who is said to be married and a mother of a teenager - has since resigned from Nimrod.

He added that Lim's only wrongdoing was his "personal indiscretion" and said the state is not responsible for policing marital vows.

Ms Pang, who is in her 40s, is expected to take the stand as a witness for the prosecution.

Lim faces nine other charges of corruption but these have been stood down and will be dealt with separately.

They involve sex with Ms Esther Goh of IT firm NCS and Ms Lee Wei Hoon of Singapore Radiation Centre.