Russia on Thursday reported more than 20,000 new coronavirus infections and 568 deaths, a peak not seen since January, as the country battles a surging outbreak of the Delta variant worsened by a sluggish jab drive.

In total, officials reported 20,182 new cases across the country over the past 24 hours, including just over 8,500 infections in Moscow, the epicentre of Russia's outbreak.

The Russian capital also recorded 92 deaths -- the highest in one day since the start of the pandemic, according to the state-run TASS news agency.

The explosion of new cases since mid-June has been spurred by the highly infectious Delta variant first identified in India. It represents 90 percent of new infections in Moscow, the city's mayor Sergei Sobyanin has said.

The surge has prompted Sobyanin to introduce a host of measures in the Russian capital. 

From June 28, restaurants will only be allowed to accept patrons who can prove they have been vaccinated, were infected within the previous six months or provide a recent negative PCR test.

In a similar move, the governor of the Krasnodar region -- home to Russia's popular Black Sea resort city Sochi -- announced Thursday that starting July 1 hotels will only accept vaccinated guests or those with a negative test.

Earlier this month, some 60 percent of all service industry workers in Moscow -- just over two million people -- were ordered to be fully vaccinated by August 15, including taxi drivers, staff of cultural venues and restaurant workers. A number of regions are following suit.

Speaking to reporters on Thursday, Kremlin spokesman Dmitry Peskov said that despite the measures vaccination "remains voluntary". 

"It is voluntary because you can change jobs," he said.

Russia has several coronavirus vaccines that have been available for free since early December, but its campaign to inoculate its population against Covid has lagged.

As of Thursday, just 20.7 million out of a population of about 146 million had received at least one dose of a vaccine, according to the Gogov website, which tallies Covid figures from the regions and the media.

Russia, with 131,463 coronavirus deaths officially recorded, is the hardest hit country in Europe.

Under a broader definition for deaths linked to Covid, statistics agency Rosstat has counted at least 270,000 deaths since the pandemic began.