The party has three MLAs in the 40-Member Goa Assembly and its senior leader and Marcaim legislator Sudin Dhavalikar is the deputy chief minister in the Pramod Sawant government.
Speaking to new agency PTI, MGP president Dipak Dhavalikar alleged one of his party's officer-bearers was "made to issue a letter" to the governor and speaker declaring authority over entire legislative affairs of the outfit.
Dhavalikar said the MGP central committee would meet Wednesday to chalk out its future course of action, which, he claimed, can decide the fate of the state government.
"There is a larger conspiracy under which one of our senior officer bearers, general secretary Lavoo Mamlatdar, was made to issue a letter to the governor and speaker, in which he stated that he was taking over the entire authority on legislative affairs of the party," Dhavalikar said.
He said his party was the state's oldest regional outfit but some sections were opposed to its growth.
Mamlatdar had last week written a letter to the governor and Assembly speaker stating he was the sole authority in the MGP to communicate party decisions to them.
Following the letter, the MGP had expelled Mamlatdar.
Talking about Wednesday's party meeting to discuss this issue, Dhavalikar said, "We might take certain resolutions in the central committee meeting which can have bearing on the stability of the government led by Pramod Sawant."
He alleged moves were afoot by his rivals to wean away MGP MLAs Manohar Ajgaonkar and Dipak Pawaskar, and in the process isolate Deputy Chief Minister Sudin Dhavalikar.
"Any attempt to disturb our MLAs will be viewed seriously and we won't mind pulling out of the government," he said.
On being queried about whether the option of the aligning with the opposition Congress was open to the MGP, Dhavalikar replied in the affirmative.
After the demise of Manohar Parrikar, BJP's Pramod Sawant took over as Chief Minister. He heads a coalition government comprising the MGP, the Goa Forward Party (GFP) and three Independent MLAs
Sawant faced vote of confidence during which his government garnered the support of 20 MLAs: 11 from the BJP, three each from MGP and GFP, three independents. Fifteen MLAs -- 14 from congress and one from NCP -- voted against his government.
The support of three MGP MLAs is crucial as without them the strength of the coalition government will reduce to 17 in the house. The magic figure in the 40-member assembly, the strength of which has been reduced to 36 following resignations of two MLAs and demise of two including Parrikar, is 18 as of now.
Not willing to let Goa slip away, the BJP had rushed Union minister Nitin Gadkari to the state as an interlocutor to hold talks with the alliance partners and Independents, to ensure the party retains the government.
Gadkari played a key role in cobbling together the coalition in 2017, too, when the BJP failed marginally to reach the majority mark.
Goa has two Lok Sabha seats. The tiny emerald land goes for polling on April 23. Results will be declared on May 23.
(With additional information from PTI)