The Japanese government said Wednesday it will bar the entry of foreign nationals who have recently traveled to Thailand and six other countries in an effort to curb the spread of the coronavirus.

The measure will be effective from Friday. The six are Cambodia, Sri Lanka, the Seychelles, Saint Lucia, East Timor and Mongolia, bringing the number of countries and regions under such restrictions to 159.

Foreign nationals who have been to any of those areas within 14 days of arrival will not be allowed to enter Japan, with the exception of permanent residents, their families and others with special circumstances. Japanese citizens are not subject to the measure.

The government also added Sri Lanka to a list of countries it deems to pose an especially high risk of becoming a gateway for the highly contagious India variant of the coronavirus to enter Japan.

Foreign nationals, even those with resident status, are denied entry after traveling to the areas -- also including India, Pakistan, Nepal, the Maldives and Bangladesh.

Japanese citizens who have been to the countries are required to quarantine for six days at a designated facility and take multiple tests to check for infection.