Both the seats were held by Congress MLAs Dayanand Sopte and Subhash Shirodkar, before they resigned last year and joined the ruling BJP.
Another seat, Mapusa fell vacant due to the death of sitting BJP MLA Francis D'Souza.
Gaonkar said the announcement about Mapusa seat will be made shortly.
Earlier in the day, the Maharashtrawadi Gomantak Party (MGP), an ally of the ruling BJP, announced to contest bypolls to all the three Assembly constituencies.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)