The event, tentatively scheduled at the Raj Bhavan, was expected to be brief and could be held at around 4 PM, they said.
However, the official announcement to this effect is yet to be made.
Palaniswami is reportedly discussing the composition of his cabinet and the confidence vote which he has to seek in the next 15 days, as mandated by Governor Ch Vidyasagar Rao.
Earlier in the day, the Governor had met Palaniswami -- the third meeting between the two since February 14 when AIADMK
General Secretary V K Sasikala
was convicted by the Supreme Court in an assets case, dealing a body blow to her ambition of becoming Chief Minister.
She was earlier elected AIADMK
Legislature party leader on February 5, but a revolt by the O Panneerselvam
threw a spanner in the works.