India is due to announce the dates of a general election, which is likely to be held in several stages over a month.
A spokesman for the Election Commission told Reuters news agency that officials would unveil the dates at a press conference on Wednesday.
With more than 800 million eligible voters, India’s election will be the largest the world has seen.
The ruling Congress party and the main opposition Bharatiya Janata Party will be battling a host of smaller parties.
Leaders of 11 regional parties have formed a Third Front against the Congress and the BJP.
A new anti-corruption Aam Aadmi (Common Man’s) Party, which made a spectacular debut in recent polls in the capital Delhi, will also contest the elections.
The Congress campaign is being led by Rahul Gandhi, while the BJP’s candidate for the top job is the controversial chief minister of Gujarat, Narendra Modi.
India’s Lok Sabha (lower house of parliament) has 543 elected seats and any party or a coalition needs a minimum of 272 MPs to form a government.
Media reports suggest that this year’s general election may be the longest ever, and held in more stages than the five-phase poll in 2004.
The elections are likely to be held in April and May, and the results expected by mid-May.