Election Commission decided to end the campaign for Phase 7 Lok Sabha polls early.

Election Commission observers had recommended that the campaign for the last round of voting in West Bengal for the ongoing national polls should end immediately following the violence in Kolkata during a rally by BJP chief Amit Shah on Tuesday but were overruled, sources have told NDTV. The Election Commission, in an official statement however, contested this saying it was "not the observers' brief to suggest deadlines".

In an unprecedented decision on Wednesday, the Election Commission had said that parties will have to wrap up their campaign for the nine seats in the state, which will vote on May 19, by 10 pm on Thursday - 19 hours before the usual deadline.

While the BJP hailed the Commission's decision as validation of their complaint that Bengal has descended into anarchy, Chief Minister Mamata Banerjee said it was "undemocratic" and a "gift for BJP" since Prime Minister Narendra Modi had two more rallies scheduled on Thursday.

"Tomorrow, Modi has two meetings in Bengal. When he finishes, the campaigning also ends... Instead of punishing Amit Shah, the Election Commission has given a gift to the BJP," Ms Banerjee said on Wednesday, calling the decision "unethical, unconstitutional, undemocratic and biased".

Though Election Commission sources have said the last-minute window was not designed to help one particular party, NDTV has learnt that the report by poll body's central observers filed on Wednesday was not in favour of this grace period.

"The report to the Election Commission projected that the situation could further deteriorate and thus no chance could be taken. It recommended that campaigning must end instantly," a source told NDTV on the condition of anonymity.

"The three election commissioners took their considered opinion to delay the advancing of the (last) date of campaigning," the source said.

The Election Commission, which has also faced piercing opposition criticism of not taking action against PM Modi and BJP chief Amit Shah after complaints against them of using the armed forces and religious polarisation to draw votes, had taken to a rarely-used clause of the constitution to end the campaigning early but leave the gap.

In a statement to NDTV, the Election Commission of India (ECI) said it was "factually incorrect" to say the observers advised for an immediate end to the campaign. "It's not the observers brief to suggest deadlines to ECI. They were asked by ECI to give a ground report only. It's ECI's decision vide article 324 to curtail the campaign hours," it said.

The decision had come as the political fight between the BJP and Bengal Chief Minister Mamata Banerjee escalated over the vandalising of a statue of iconic 19th century reformer Ishwar Chandra Vidyasagar during Amit Shah's rally in Kolkata on Tuesday.

Both parties accused each other of inciting the violence and desecrating the statue.

Finance Minister Arun Jaitley of the BJP claimed the Commission, through their decision, has agreed about the prevailing anarchy in Bengal.