To prove that the Electronic Voting Machines (EVM) cannot be tampered with, the EVM challenge will start from 3 June, Chief Election Commissioner Nasim Zaidi said on Saturday.

"The ECI throws opens the challenge to all national and state political parties from 3 June onward," Nasim Zaidi said, adding "The ECI through this challenge will restore and enhance faith and confidence of voters in EVM voting system."

"EVMs are open for visual inspection during the challenge too," Zaidi said, adding, "It will be a failure on part of the challenger if the EVM turns non-operational upon tampering attempt; results match with control unit and challenger defies norms or withdraws."

For the EVM challenge, political parties will have to apply by 26 May.

The Election Commission said it is just to reassure political parties that have raised doubts about the machines used to conduct every Lok Sabha and state elections held after 2002.

To bring more transparency in the voting system, Zaidi said that all future elections will be held with VVPAT and EVMs across all polling stations.

"All future elections will be held with VVPAT along with EVMs across polling stations," Zaidi said, adding, "Manipulation of EVMs at manufacturing stage is totally rolled out due to stringent security measures."

"Complaints came after elections in 5 states, but we did not receive credible material information on EVM tampering from complainants," he added.

"People who questioned reliability of EVMs have not yet submitted any proof or credible material to support their claim," he further said.

Brushing aside the EVM tampering allegations, the Election Commission of India (ECI) demonstrated the working of Electronic Voting Machines (EVMs) and Voter Verifiable Paper Audit Trail System (VVPATs).

The Bharatiya Janata Party (BJP) on Friday said that the live demo of EVMs and VVPATs by the ECI will ensure credibility and the authenticity of the voting machine will be retained.

While earlier in the week, the poll panel had said it would offer an 'opportunity' to the political parties to prove that EVMs used in the recently held assembly polls were tampered with or can be tampered even with laid down safeguards.

The ECI also convened an all-party meeting over the issue of EVM and other electoral reforms.

(With inputs from agencies)