TOKYO, Japan -- Japan is set to approve new coronavirus restrictions on a large part of the country, including Tokyo, on Wednesday as it battles record infections fuelled by the Omicron variant.

Final approval from the government is expected later in the day, but on Wednesday morning experts backed placing 13 regions "under quasi-emergency measures from January 21 to February 13" Daishiro Yamagiwa, minister in charge of the coronavirus affairs, told reporters.

The move allows each region to decide what specific measures to implement, but local media said the restrictions were likely to include shorter opening hours for bars and restaurants and possible restrictions on alcohol sales.

The highly infectious Omicron variant is driving a resurgence in coronavirus cases, with daily nationwide infections topping 30,000 for the first time this week, according to media tallies.

Japan has still been less hard hit than many countries, with around 18,400 deaths in the pandemic while avoiding strict lockdowns.

But government officials and experts are worried that rising infections could put pressure on the country's medical system.

Three Japanese regions are already under virus restrictions, after surges in cases linked to US military bases.

More than 78 percent of Japan's population is fully vaccinated, but the programme began later than in some other developed countries.

So far, just 1.2 percent of the population has received a booster shot.