* Current lockdown measures expire on April 30
* PM asks government for proposals on easing restrictions
* Head of safety watchdog says lockdown should continue to May 12
* Authorities report more than 6,100 new coronavirus cases (Adds details, quotes, background)
By Katya Golubkova and Anastasia Lyrchikova
MOSCOW, April 27 (Reuters) - Russia overtook China in the number of confirmed coronavirus cases on Monday when its tally climbed above 87,000, as pressure rose on the government to consider easing lockdown restrictions for businesses to help shore up the rattled economy.
Russia, the world's largest country by territory, has been on lockdown since President Vladimir Putin announced the closure of most public spaces on March 25. These measures are due to expire on April 30 and Putin has not yet said if he plans to extend them.
Anna Popova, the head of Russia's safety watchdog Rospotrebnadzor, told state television on Monday that, in her view, restrictions should be in place until May 12.
Earlier Prime Minister Mikhail Mishushin asked his government to submit proposals by Thursday to ease some of the restrictions on businesses. Many firms have warned that they risk going bankrupt if the lockdown continues, and thousands of jobs have been laid off.
"As soon as situation will be changing for good, we would need to consider a step-by-step cancellation of restrictions on certain companies... operations," Mishustin told an online government meeting.
On Monday, the authorities reported 6,198 new cases of the new coronavirus, bringing the total to 87,147, with 794 deaths.
Russia, one of the world's top oil and gas exporters, is particularly vulnerable to the spread of the coronavirus at production sites. Most are located in remote areas accessible by only air, meaning the workers in close proximity, increasing their risk of infection.
Citing local officials, Interfax said on Monday that an airport in Sabetta in the northern Yamal peninsula had been shut down for quarantine after cases of the new coronavirus were detected at the Yamal LNG production site controlled by Novatek .
A total of 143 cases were confirmed in Sabetta, the local crisis response center said separately.
In the northwestern region of Murmansk where Novatek is building a plant to supply its next LNG project, the Arctic LNG 2, over 800 workers tested positive for coronavirus, the local crisis response centre said on Sunday.
Velesstroy, a sub-contractor for the plant, temporarily suspended work at the site near Murmansk but said in a statement to Reuters that the project will remain on schedule.
To limit the risk of contagion at over 1,000 power plants in Russia, including nuclear ones, over 200,000 employees - or nearly a third - were recently tested for the virus, the energy ministry said.
It did not say how many of those tests returned positive.
Mainland China, where the new coronavirus first emerged, reported a total of 82,830 cases on Monday. China is now fighting an increased number of new cases coming from Russia. (Reporting by Gleb Stolyarov, Maria Tsvetkova, Anton Zverev, Vladimir Soldatkin and Anastasia Lyrchikova Writing by Katya Golubkova Editing by Raissa Kasolowsky)