Ramos-Horta succeeded following two rounds of elections in April and May, beating out seven other candidates vying to lead the country.
Ramos-Horta is currently the country's Prime Minister, but will vacate this position before next month's parliamentary elections.
United Nations Secretary-General Ban Ki-moon today yesterday congratulated Ramos-Horta on his victory.
"Like the people of Timor-Leste, the United Nations looks to Dr. Ramos-Horta to lead the country in confronting the challenges ahead, from security reform and justice to development and governance," he said.
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