The U.S. embassy in Hanoi has not explained why his visa application has been rejected twice.

A 12th grader from central Vietnam is likely to miss his chance to compete at an annual science fair in the U.S. next week due to visa issues.

Mai Nhat Anh from Phan Boi Chau High School in Nghe An Province and his supervisor Mai Van Quyen are preparing for yet another visa application so that they can hopefully fly to the U.S. on May 11 to attend the Intel International Science and Engineering Fair (Intel ISEF) two days later.

Anh and another student, Phung Van Long, have been working on a project to distill salt water under guidance of their teacher, Quyen.

Mai Nhat Anh (R) and Phung Van Long (L) with their supervisor Mai Van Quyen. Photo by VnExpress/Nguyen Hai

The project won first prize at a national science and technology competition held by the education ministry in March.

Their invention is one of seven other projects chosen for the Intel ISEF this year.

At present, the U.S. Embassy in Hanoi has only granted visa for Long and has rejected Anh and Quyen's applications twice.

“We don’t know why we have been rejected because the embassy has not given us an explanation,” Quyen said.

This is not the first time a Vietnamese student has encountered this situation.

Last year, Pham Huy, a high school student from central Vietnam, also had two visa applications rejected to attend the fair in the U.S.

After the third interview, which followed special requests from Vietnam's government and widespread media reports, he finally made it and claimed third prize for a robotic arm invention for disabled people.

Intel ISEF is the world’s largest international pre-college science competition.

Each year, approximately 1,800 high school students from more than 75 countries, regions, and territories are awarded the opportunity to showcase their independent research and compete for an average $4 million in prize money./.

VNF/Vnexpress