The Congress on Friday accused the BJP of being an anti-Christian party, saying the saffron party was trying to enter Christian-dominated Mizoram "through backdoor" after the November 28 elections in the state.
Christians constitute around 87 per cent of the population of Mizoram, according to the 2011 Census.
Mizoram is the only state in the northeast where the Congress is in power.
"The BJP is against minorities and the Christians... The party has brought intolerance and hatred against Christians and other minorities," Congress general secretary Luizinho Faleiro told reporters.
He asked why did the BJP choose to observe Good Governance Day on December 25, when it seeks to celebrate the next Christmas in Mizoram under its rule.
The senior Congress leader was referring to BJP president Amit Shah's statement in a rally here last month that he "was reassured that the next Christmas Mizoram celebrates will be a Christmas under a BJP government."
In 2014, the BJP-led central government had decided to observe December 25, the day of Christmas celebrations, as national Good Governance Day.
December 25 is also the birthday of former Prime Minister Atal Bihari Vajpayee.
Faleiro alleged that the BJP has been "trying to enter Mizoram politics through backdoor by using the MNF as they had done in other northeastern states".
The opposition Mizo National Front (MNF), led by former chief minister Zoramthanga, is a constituent of the North East Democratic Alliance (NEDA) headed by the saffron party, he said.
NEDA is a political coalition formed by the BJP and regional political parties of the northeastern states in 2016.
The Congress has been alleging that the MNF would form a post-poll alliance with the BJP in the event of a hung assembly.
However, both the parties denied it.
The ruling party also alleged that the BJP would indulge in horse-trading after the assembly polls to "grab power at all costs" and Independent MLAs would be the most vulnerable in that scenario. The BJP has denied this charge too.
The Zoram People's Movement (ZPM), a conglomerate of two political parties and five other organisations, also faced the attack of the Congress as its 35 candidates are contesting the polls as Independents.
The ZNP on Friday said it would not form a pre-poll or a post-poll alliance with the BJP.
The foundations of the ZPM were safety of the land, the people and religion, and there was no scope for an alliance with the saffron party, ZPM senior vice president Dr Kenneth Chawngliana said.
He said the 35 ZPM candidates had to contest as Independents as the party was formed hardly a year ago and had never contested elections in the past.
"We would be recognised by the Election Commission and allotted a symbol only after contesting and have a requisite number of legislators or share of votes," he said.
He said the ZPM nominees signed a pledge and also announced chief ministerial candidate before the election.
