Rajapaksa, 70, defeated Sajith Premadasa, 52, by more than 13 lakh votes, the election commission announced on Sunday.
Gotabaya oversaw the military defeat of Tamil separatists under his brother Mahinda 10 years ago
His statement came as a spokesman for Rajapaksa claimed that the 70-year-old retired lieutenant colonel had won Saturday's vote, before the final results were formally announced
The winner of its upcoming presidential elections could alter the nature of India's relationship with that country
The company has 809 screens at 171 properties in 70 cities in India.
Rahul Jacob visits Sri Lanka once more. Why he can't get enough of the warmly welcoming country
In an interview, he tells Aditi Phadnis about the new challenges Sri Lanka faces after the April attacks by Islamic radicals
High visa charges is one reason that makes India less attractive to tourists and so the fee is being reduced to increase footfalls and foreign exchange receipts
The island nation's tourism sector, one of the country's top revenue streams, suffered a massive blow following April 21 Islamist militant bombings of churches and luxury hotels
Maldives ($9,310 or Rs 6,36,432) and Sri Lanka ($4,060 or Rs 2,77,542) are the only two countries in South Asia in the upper-middle-income group
Allowed to detain and interrogate suspects without court orders, Sri Lanka's police and military have arrested more than 100 suspects in the crackdown after the Islamist militant attacks
To lure tourists back, Sri Lanka is hosting international sporting events and has mothballed a rule on minimum rates for hotel stays
Although Sirisena has not so far declared his intention for a re-run, his souring of relationship with the Prime Minister, Wickremesinghe, has indicated that the UNP will be fielding its own candidate
Sri Lanka estimates that it will lose about $1.5 million in revenue this year as a result of a sharp dip in tourist arrivals following the April 21 suicide bombings
Homes and mosques were also vandalised by large groups of people armed with sticks and blunt weapons
Mohamed Aliyar, 60, is the founder of the Centre for Islamic Guidance, which boasts a mosque, a religious school and a library in Zahran's hometown of Kattankudy, a Muslim-dominated city on Sri Lanka
The arrests have come after the Sri Lankan government beefed up security measures following the country's worst terror attacks on Easter Sunday
Defence Secretary Fernando handed over his resignation letter to President Maithripala Sirisena Thursday
'When in Sri Lanka, choose trains', says the author
The envoy said that there are also logistical issues like what all and how much the refugees can take along with them, and how they will be taken back