A higher court in the eastern city of Kolkata on Wednesday ordered India's top poll panel to preserve all voting machines in an election petition filed by Bengal Chief Minister Mamata Banerjee over her defeat in May's assembly polls.

The Kolkata High Court also issued a notice to Bengal's main opposition leader Suvendu Adhikari of the Bharatiya Janata Party (BJP) in the case lodged by Mamata challenging the election of her former protege-turned-rival from Nandigram in the assembly polls.

"Justice Shampa Sarkar asked the Election Commission of India to preserve all records, and devices, such as electronic voting machines and video recordings, apart from issuing the notice to Suvendu," Mamata's lawyer Sanjay Basu told the media.

Justice Sarkar took over the case from another judge against whom the Bengal Chief Minister had levelled allegations of "conflict of interest" in the wake of his alleged links with India's ruling BJP.  

But before quitting the case, Justice Kaushik Chanda had imposed a fine of 5 lakh rupees (7,000 USD) on Mamata for her "preplanned move to malign a judge".

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On May 2, Mamata single-handedly pulled off a landslide victory in the assembly election for the third time in a row, bucking anti-incumbency and staving off a massive challenge from Prime Minister Narendra Modi's BJP.

Though her Trinamool Congress party swept back to power with a resounding majority, Mamata lost her own seat in Nandigram to BJP's star campaigner Suvendu by a thin margin of 2,000 votes.

Last month, Mamata moved the high court to declare Suvendu's election win null and void on the grounds that he had indulged in corrupt practices and sought votes on the basis of religion. 

"Suvendu Adhikari has indulged in several corrupt practices that have enhanced his winning chances and materially altered Mamata Banerjee's chances of success in the election," her petition read.

In her petition, Mamata also alleged discrepancies in the counting of votes, Mamata's lawyer had said.

Though Mamata had conceded defeat to Suvendu in Nandigram -- the potboiler of the assembly election in Bengal -- the Trinamool supremo said on the counting day only that she would challenge the result in a court of law. "I will move the court against Suvendu's win," she had said.

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West Bengal had witnessed the most high-profile contest in India's recently held state elections. While Mamata harped on being Bengal’s daughter, the BJP asked people to vote for "change and socio-economic development" after nearly 50 years of Communist and Trinamool Congress rule.