PM Modi was supposed to address the mega gathering on February 2. (File)

The BJP has decided to shift the venue of Prime Minister Narendra Modi's rally in North 24 Parganas' Thakurnagar, as the site where it was scheduled to be held has been booked by the Trinamool Congress.

The ground, where PM Modi was supposed to address the mega gathering on February 2, has been booked by Mamata Banerjee's party for a week-long religious programme.

According to BJP leaders, the venue was also not big enough and did not meet the security requirements.

"We will organise the rally on February 2 at Thakurnagar but the land or the venue where we were supposed to organise it has been changed and it has been shifted to another a nearby ground," BJP state president Dilip Ghosh told PTI.

"It has been done mainly due to two reasons - the new ground is much bigger than the previous one and secondly TMC had already booked the previous venue for religious programme. So we didn't want to take any risk," he said.

The Special Protection Group, which guards the prime minister, was also not happy with the previous venue as it did not meet the security requirements, Mr Ghosh said.

The BJP-aligned faction of All India Matua Mahasangha is organising the rally. PM Modi's proposed rally is of immense political significance as the area is known as the hub of Matua community and is near the house of its matriarch Binapani Debi.

Matuas with an estimated population of three million in Bengal exhorts influence in at least five Lok Sabha seats in North and South 24 Parganas districts.

The community originally hails from East Pakistan (now Bangladesh). Matuas started migrating to West Bengal beginning 1950s, mostly due to religious persecution there.

Mr Ghosh alleged, "Whenever we try to organise any rally, the TMC tries to create hurdles. This time too there has been no difference. So we decided not to take any chance."

The Trinamool Congress denied the charge and called the allegation "baseless".

"The allegation is baseless. We had obtained police permission for using microphone on the ground for our religious fair between January 28 and February 5 long time back," said Trinamool Congress MP Mamata Thakur, who heads a faction of the Matua Mahasangha.

According to BJP sources, this will be one of the areas where the party will campaign about the Citizenship Bill, which was passed in the Lok Sabha on January 8.

The Bill seeks to grant Indian citizenship to non-Muslims who fled religious persecution from Bangladesh, Pakistan and Afghanistan, and entered India before December 31, 2014.