Ukraine has dismissed claims that it is planning to attack a nuclear plant "insane Russian propaganda".
Moscow has suggested that Kyiv want to storm the Kursk nuclear power plant and developing a "dirty bomb".
The Russian defence ministry alleged Ukraine would blame Moscow for the detonating a device to spread radioactive material.
Ukrainian foreign office spokesperson Heorhii Tykhyi said the accusations were "dangerous lies".
He added: "We are witnessing another surge of insane Russian propaganda."Ukraine has neither the intention nor the ability to carry out any such actions. Russia must stop spreading dangerous lies. Ukraine has always been and remains a loyal member of the NPT (Non-proliferation treaty).
"We do not have any 'dirty bombs' and do not plan to acquire them."
Russian President Vladimir Putin alleged Ukraine was planning such an attack after launching the invasion of Ukraine in February 2022.
Russia also alleged a Ukrainian drone dropped an explosive charge on a road outside the Zaporizhzhia nuclear power plant in Ukraine on Saturday.
Fighting around the area has led to claims by both sides that they are risking a nuclear disaster.
