Supporters of Narendra Modi, prime ministerial candidate for India's main opposition Bharatiya Janata Party (BJP), cheer as Modi arrives at the airport in New Delhi May 17, 2014.[Photo/Agencies]

Hailing the party's victory, BJP chief Rajnath Singh said it marked a "new era" for India as people vented out their frustration against the Congress' 10 years of misrule. "We will now rewrite India's success story," he told the media at the party headquarters in the national capital.

Congress President Sonia Gandhi and her 43-year-old son Rahul Gandhi, who was party's prime ministerial candidate, accepted moral responsibility for the grand old party's worst ever defeat in general elections, but also congratulated the BJP for the massive win.

"I personally take responsibility for the party's defeat," said Rahul Gandhi, whose party managed to get barely 44 seats on its own and less than 60 with its allies in the United Progressive Alliance.

World leaders who congratulated Modi on his win included Pakistani Prime Minister Nawaz Sharif, British Prime Minister David Cameron and Australian Prime Minister Tony Abbot.

"Congratulations @narendramodi on victory in India's elections. Keen to work together to get the most from UK-India relationship," tweeted Cameron, who was among the first world leaders to greet Modi.

Experts said that though Modi is accused of keeping mum during the 2002 communal riots of Gujarat, in which over 1,000 people, mainly minority Muslims, were killed, he is perceived as a no- nonsense, can-do leader who stands for development and muscular nationalism.

"Despite such allegations against him, Modi campaigned on promises he would revive the country's slowing economic growth. So, the people trusted him. Moreover, the Congress faced anti- incumbency due to its failure to tackle corruption and inflation," said Delhi-based Prof. Ajay Singh.