The U.S. Centers for Disease Control and Prevention has revised its travel recommendations for Japan, as the country's Covid-19 immunization efforts picked up steam Thursday.

Reflecting the latest evaluation by the centers, the department has returned Japan from Pandemic Level 4 to Level 3, indicating a trajectory to which U.S. citizens should "reconsider travel," Kyodo News reported.

Although the risk is still high, the centers said it does not strictly recommend against it for vaccinated people.

The centers has also loosened travel restrictions for more than 110 countries and territories, ahead of the Tokyo Olympics.

Tokyo is set to host the games, which were initially scheduled last year, but canceled because of the coronavirus pandemic, starting July 23.

Many local governments in Japan are set to expand their Covid-19 vaccine distribution to those below 65 years old this month, and preparations are underway for on-site vaccinations at schools, offices and other business establishments.

According to a centers' representative, another 50 countries and territories have been lowered to Level 2 or Level 1. Countries ranked lowest for Covid-19 risks now include Singapore, South Korea, Israel, Belize, Iceland and Albania.

Countries that are now listed at Level 3 are France, Canada, South Africa, Philippines, Ecuador, Mexico, Spain, Russia, Turkey, Switzerland, Honduras, Ukraine, Italy and Hungary.

New cases of the virus have been dropping in Tokyo over the past several weeks, The Associated Press said.

Japan has reported 2,242 new Covid-19 infections Wednesday, 175 fewer compared to the same day last week, the World Health Organization and public broadcaster NHK, said.

Overall, Japan has reported around 14,000 Covid-19 deaths, decent in terms of global standards but not as good as some Asian neighbors, the AP reported.