A key regional leader broke away from India’s opposition alliance on Sunday and was set to join hands again with Prime Minister Narendra Modi’s Bharatiya Janata Party (BJP), in a major blow to Modi’s challengers months before general elections.

According to local media reports, Nitish Kumar, chief minister of the northern state of Bihar, tendered his resignation to the state governor.

Kumar told news agency ANI that not everything was alright with the alliance.

“Today, I have resigned as the chief minister and I have also told the governor to dissolve the government in the state. This situation came because not everything was alright,” Kumar said.

Kumar’s departure weakens India’s opposition parties which had decided to set aside their differences last year to form an alliance called ‘INDIA’ to take on the BJP in general elections due by May.

Kumar was instrumental in bringing together opposition parties to form the 28-party alliance, which includes the main opposition Congress party.

Congress spokesperson Jairam Ramesh said that the BJP was scared of the alliance and this “political drama had been created” to divert attention.

The alliance was already facing serious turbulence last week with member Mamata Banerjee, chief minister of the eastern state of West Bengal and the head of Trinamool Congress party, saying it will contest Bengal alone.

Similarly, another member, Aam Aadmi Party (AAP), which rules the national capital territory of Delhi and northern state of Punjab, said it will not ally with Congress in Punjab.