Last Friday, Sunai was ordered to immediately leave his top post at the Department of Special Investigation and start working at a newly-formed agency on Monday.
His abrupt transfer has attracted criticism.
Sompong, however, has insisted he transferred Sunai because his capabilities were needed at a new agency.
When asked whether Sunai would be the last official to face a transfer ahead of normal reshuffle in October, Sompong said, "I don't know. It depends on the situation and people involved".
Sompong said he did not intend to transfer any official but would do so in order to ensure that work could flow smoothly.