Speculations were rife that Kamat may be inducted into the BJP and given a major position in the state government, considering Chief Minister Manohar Parrikar's deteriorating health.
Kamat was second in command in the BJP till 2005 when he switched over to the Congress.
The senior Congress leader, who held reigns of the state from 2007 to 2012, left for Delhi on Sunday.
"I am leaving for Delhi on a business trip. It is purely personal," Kamat said before boarding the flight to Delhi from the Goa airport.
Goa Pradesh Congress Committee president Girish Chodankar accused the BJP of spreading rumours about Kamat.
"This is a game plan of the BJP's dirty tricks department which is spreading rumours to malign the image of Kamat and the Congress," he said.
Chodankar also alleged that the BJP was trying to scare its own alliance partners with such speculations.
"Kamat is very much in the Congress and he will continue with the party," he added.
Meanwhile, Goa BJP president Vinay Tendulkar refused to comment on reports in a section of media that the issue of Kamat joining the saffron party was discussed during its MLAs' meeting held in Panaji on Saturday.
The health of 63-year-old Parrikar, who is suffering from a pancreatic ailment, deteriorated on Saturday, sparking hectic political activities across parties in the coastal state.
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