The GFP Sunday withdrew support to the BJP government in Goa by sending a communication to Governor Mridula Sinha.
The decision was taken after the Goa Foward Party held a meeting in Goa capital Panaji.
All three members of the GFP, including Vijai Sardesai who was deputy chief minister in the Pramod Sawant cabinet, were dropped and replaced by three of the 10 lawmakers, who last week switched over from the Congress to the BJP.
"The political affairs committee and the legislature party wing of Goa Forward Party met today and decided unanimously to withdraw support to the Bharatiya Janata Party government led by Dr Pramod Sawant," the party's letter to the governor read.
The BJP currently has 27 lawmakers in the 40-member Goa Assembly.