The tussle between governor C.V. Ananda Bose and the Mamata Banerjee government took a new turn on Saturday over the swearing-in of Trinamul MLA Nirmal Chandra Roy who recently won the Dhupguri Assembly bypoll.

The September 5 bypoll was held as the seat had fallen vacant following the death of BJP MLA Bishnupada Roy in July. Nirmal Roy won with a margin of 4,309 seats.

Sources said that after his win, Sovondeb Chattopadhyay, the state parliamentary affairs minister, wrote to the governor for the swearing-in.

On Saturday, sources in Raj Bhavan said the MLA had been called there to take oath around 4.30pm.

“The responsibility is with the governor but as a convention, he delegates it to the Speaker, who in turn conducts the swearing-in. In this case, the state government was not informed and the MLA reportedly was contacted directly,” said a source.

Roy eventually didn’t turn up at Raj Bhavan.

“I don’t have any information on this. Our legislative party leaders and senior ministers would speak on the issue,” Roy said at his Dhupguri residence.

A Trinamul leader said Roy was asked not to turn up for the swearing-in at Raj Bhavan till the party instructed him to do so.

A Trinamul source said that the governor's office reportedly contacted Speaker Biman Bandopadhyay to arrange the ceremony at the Assembly in the presence of the governor but that could not be done as the Assembly is closed for the weekend.

Chattopadhyay said the governor's direct intervention in the swearing-in of an MLA went against ethics.

"I sent him the letter about the swearing in of the Dhupguri MLA within days of the election result (on September 8). He deliberately bypassed me and contacted the MLA directly. It goes against the ethics of parliamentary affairs. I will speak to chief minister Mamata Banerjee and give a befitting reply to him (governor)," said Chattopadhyay.

The minister alleged that the governor intentionally created the trouble over the swearing-in of the Dhupguri MLA.

"It is unfortunate that the governor is making a small thing complex," he added.

Samik Bhattacharya, the BJP's chief spokesperson in Bengal, said the governor did not do anything unethical.

"There is nothing unethical if the governor wants to conduct the swearing-in of an MLA. I think it would be prestigious for the MLA and people of Dhupguri,” he said.