Amid media reports that he is "expected" to step down, SMRT CEO Desmond Kuek sent an email to SMRT employees last week to deny the rumours.
In an email to SMRT employees on Jan 19 seen by Channel NewsAsia, Mr Kuek said that even though it is not usual practice to comment on market rumours, a Straits Times report on his potential resignation has "generated ground concern that must be addressed".
"I would like to assure you that when I do (step down), one day as we all must for leadership renewal, you will hear about it from me first. It will not be through some speculative piece in the newspapers," he wrote.
"For now, my focus is to work with everyone toward our goals. Let’s stay on track, with everyone on board, so that we can be on top again very soon."
Mr Kuek also dismissed the rumours on Thursday on the sidelines of an SMRT event.
The Straits Times reported last week that SMRT's vice-president of corporate communications Patrick Nathan had quit and "observers are expecting chief executive Desmond Kuek to step down as well".
SMRT's management has been under fire for a spate of major train disruptions and incidents, including a collision at Joo Koon MRT station and the flooding of a train tunnel at Bishan.