Yonladee Phiyatat (standing left) presents the bottle-sorting machine project designed by her team at Satri Ranong School, Rayong province, in this undated photo from her Facebook page.

A stateless 17-year-old student thanked authorities for giving her Thai citizenship so she could participate in an international academic contest in the United States next month.

Late on Wednesday night, Yonladee "Ploy" Phiyatat posted on her Facebook page a photo of the letter she received from Arthit Boonyasopat, director-general of the Provincial Administration Department.

According to the letter, dated on Wednesday, she is qualified to obtain Thai citizenship so she could join an international contest since she has certification from a government organisation and has lived in Thailand for at least 10 years.

Mr Arthit wrote she could bring his letter to Ranong's Muang district office to apply for case-by-case citizenship approval.

According to earlier reports, Miss Yonladee was born to a Myanmar couple who had lived in Muang district of the southern province of Ranong for about two decades. They import fish to Thailand for a living.

She and schoolmates at Satri Ranong School won a national award for their automatic bottle-sorting machine project. They were invited to attend the Genius Olympiad in New York starting on June 17.

On Monday, Miss Yonladee wrote on Facebook she was born in Thailand and wished to use her capabilities to help develop the country.

As she was stateless, she was not allowed to leave the country. Her previous application for a travel document for aliens was processed slowly and she risked being excluded from the event.

The approved citizenship would pave the way for her US visa application that would allow her to join the Genius Olympiad.