A survey of South Korean students has shown a decline in academic ability amid suspension of face-to-face classes due to coronavirus pandemic, the country's Education Ministry has said.

The ministry conducted the annual survey in November last year among 3 percent of the third-grade students of junior high schools and the second-grade students of high schools, releasing the result last week.

File photo shows a high school teacher giving an online lecture in Seoul on April 9, 2020, amid the spread of the new coronavirus. (Kyodo)

The rate of the students who were judged to "have not reached the basic academic standard" increased from the previous year. The ministry said the rate rose as students had attended for only about half of the number of school days last year compared with a normal year.

In a bid to block the spread of coronavirus infections, the ministry has switched the classes at schools to online learning for a certain period and also restricted the number of students attending schools.

According to the result of the survey conducted by testing Korean, mathematics and English, the percentage of the lowest level of four classifications, which indicates not reaching the basic academic standard, increased to 8.6 percent in English from 3.6 percent the previous year among the second-year high school students.

The percentages of the lowest level in other subjects, regardless of the grades, also rose.

The ministry officials said they take the results seriously and aim to implement measures to recover academic performance.

The survey result showed an overall downward trend for the first time since the current survey method was applied in 2017.

According to another survey conducted at the same time, students' enthusiasm for learning and level of happiness in school life also declined compared with the year before.

In response to the result, Deputy Prime Minister and Minister of Education Yoo Eun Hae said online learning has a limitation in replacing school classes.

Yoo said she will discuss with health authorities on coronavirus preventative measures to let all students attend schools from the second semester that begins in August or September.