India's right wing opposition has repeatedly been declaring their vote of confidence in front-runner Narendra Modi's decisive victory in the world's biggest general election, Agence France-Presse reported.

"There's no need to wait until the 16th as the people have already decided," a confident Modi told supporters a week ahead of the announcement of results from a marathon election.

"It will be a Modi government this time. Good days are ahead of you," he added in a rally in the northern state of Uttar Pradesh, which will host part of the final round of voting on Monday.

Although most of the seats are widely expected to be won by Modi's Bharatiya Janata Party, it is unlikely to gain a majority on its own in the 543-seat parliament.

BJP will need new allies to form the government, some analysts said. However, the final days of the election contest had witnessed several potential allies distancing themselves from the prime candidate.

But Modi's top aide Amit Shah quashed any suggestion on Friday that his boss might step aside after the elections for a compromise candidate that would be acceptable to other parties who have cool relations with Modi, AFP reported.

"The NDA will get more than 300 seats in these elections," Shah said in reference to an existing BJP-led opposition grouping in parliament known as the National Democratic Alliance.

"We will get a clear majority and our prime ministerial candidate Narendra Modi will be the prime minister," Shah added in comments carried by the CNN-IBN network.

Modi faces a threat of being thwarted if leaders of powerful regional parties decline to do business with him, even if the ruling Congress party gets ousted after a decade in power.

One potential partner, Bahujan Samaj Party (BSP) leader Mayawati, told reporters on Friday that she would not countenance any deal with Modi.

"I want to make it clear that BSP will not extend any kind of support to NDA at any cost," said Mayawati, a champion of India's lower caste dalits, whose party currently has 21 MPs and has its power base in Uttar Pradesh.