Indian Prime Minister Narendra Modi has promised to build a strong and inclusive nation after his ruling Hindu nationalist party headed for a landslide win in the South Asian country’s marathon general elections.

"Together we grow. Together we prosper. Together we will build a strong and inclusive India. India wins yet again!," Modi tweeted Thursday as the outcome of the world�s biggest election became clear.

India is counting about 600 million votes after its seven-phase elections drew to a close on May 19, with early leads indicating the return of Modi for a second term. 

Official data from India’s Election Commission showed on Thursday the National Democratic Alliance (NDA) led by the Hindu nationalist Bharatiya Janata Party (BJP) was leading in nearly 340 of the 542 seats. 

The opposition United Progressive Alliance (UPA) headed by the Indian National Congress (INC) is leading in less than 100.

A party or coalition needs 272 seats in India’s lower house of parliament, or the Lok Sabha, to form a government. The lawmakers from the winning party or coalition elect their leader, who then becomes the country�s prime minister.

Following the results, celebrations broke out at BJP offices, including in the Indian port city of Mumbai, where a few hundred BJP supporters played drums and waved party flags.

Exit polls predict win for incumbent Indian PM Modi

Indian Prime Minister Narendra Modi’s ruling alliance led by the right-wing Bharatiya Janata Party (BJP) is likely to win a majority in the parliament, according to exit polls.

Running up to the polls, Modi faced such challenges as strong opponents, particularly a resurgent leader of the opposition Congress Party Rahul Gandhi whose father, grandmother, and great-grandfather had all been former prime ministers.

Modi’s party won a historic landslide in the last elections in 2014, the first absolute majority in three decades.

His popularity remains vast as many Indians credit him with programs that have helped the poor and cut through red tape and corruption.

Modi faced criticism early on in the campaign for failing to create jobs for the youth. But he turned the campaign into a fight for national security after tensions rose with Pakistan.

Pakistan PM congratulates Modi

Pakistan�s Prime Minister Imran Khan congratulated Modi and his party on their election victory, saying he looked forward to working with the premier for "peace, progress and prosperity in South Asia".

"Congratulate Prime Minister Modi on the electoral victory of BJP and allies. Look forward to working with him for peace, progress and prosperity in South Asia," Khan tweeted Thursday.

Khan’s message came just hours after Pakistan�s military tested a surface-to-surface ballistic missile capable of carrying conventional and nuclear warheads.  

The launch followed an announcement by India a day earlier that its military had test-fired BrahMos missile, which is capable of delivering nuclear warheads.

Pakistan has watched Modi�s election campaign warily, frequently accusing him of fanning recent tensions in the disputed Kashmir region, which brought the two nations to the brink of war in February, as a ploy to gain votes.

Last month, however, Khan said a Modi win could help settle the Kashmir issue.