Russian and Ukrainian peace negotiators held a 90-minute video call on today and working groups will continue to meet throughout the day, a member of the Ukrainian delegation said.
The Kremlin said the talks had made no significant progress as yet, although Ukrainian delegate and lawmaker David Arakhamia was quoted in the Ukrainian media saying that they would be "working the whole day".
Ukraine started the day by defying a Russian demand that its forces lay down arms before dawn in Mariupol, where hundreds of thousands of civilians have been trapped in a city under siege and already laid to waste by the bombardment.
And concern has been raised after Ukrainian state nuclear company Energoatom warned that radiation levels around the occupied Chernobyl nuclear plant risked rising, because its radiation monitoring system and forest firefighting service were not working.
Soon after launching an invasion on February 24, Russian forces took control of the territory around the now-defunct power plant that was the site of the world's worst nuclear accident in 1986.
As a result, the system monitoring radiation levels in the 30km so-called exclusion zone in the forests around the plant is currently not working, Energoatom said in a statement.
"There is no data on the current state of radiation pollution of the exclusion zone's environment, which makes it impossible to adequately respond to threats," it said.
It said seasonal forest fires, which occur most often in spring and summer, posed a particular threat as the zone's forest fire service was unable to work.
"Radiation levels in the exclusion zone and beyond, including not only Ukraine, but also other countries, could significantly worsen," it said.
The Chernobyl nuclear plant was an early strategic target for the Russian forces and fell on the first day of the invasion with employees since working long shifts and under extreme pressure.
Earlier this month the Mirror reported that the Intelligence Directorate of the Ministry of Defence of Ukraine believes Putin is planning a 'technological catastrophe' at the power station.
Intel chiefs warned that the disaster will be blamed on the Ukrainians and said Putin is prepared to commit 'nuclear blackmail' on the world if his invasion fails.
