Restored fresco had been stored in Voronezh museum's basement for a century before public display.
Ambassador Anatoly Viktorov stated that Moscow has evidence that Trufanov's condition is not good, adding, "We hope that in the remaining few days, his health condition will not worsen."
The FSB said it had seized components for a homemade explosive device and that investigators in Sverdlovsk had opened a criminal case.
A new assessment of the situation will be conducted next week, and a decision will be made as to whether operations on the route will resume.
Photographs posted on Russian Telegram channels showed a shattered entrance to a building littered with rubble and two bodies lying in the blood-stained snow.
Moscow also continued withdrawing military equipment from bases across Syria, as reported last week by The Jerusalem Post.
Both "cat" tiles have already been restored and are now being prepared for transfer.
Russians claimed the American citizen had provided intelligence for two years.
Rutte on Wednesday said the 'victory plan' presented by Ukrainian President Volodymyr Zelenksy on Wednesday was a good signal, but that he was not able to support it as a whole as things stand.
Analysts warn that removing the Taliban from the terror list might not curb threats from extremist groups like IS-KP