The Government Office's communication director, Urmas Seaver, said on Thursday evening that the organizing team of Estonia 100 had proposed the prime minister attend the Estonian culture days in the Siberian city from May 16 to 21 this year.

Ratas considers the Estonia 100 global events series to be important for Estonian communities around the world, Seaver added. But in light of the recent developments connected to the poisoning of former Russian intelligence officer and double agent Sergei Skripal and his daughter in the English city of Salisbury, Ratas' participation in the Krasnoyarsk events is not possible.

The prime minister said in the Riigikogu on Wednesday that Estonia condemns Skripal's poisoning, which Russia is suspected of having carried out. The incident is serious, Ratas said.

"We trust the information that's coming from our British allies in the case of this investigation," Ratas said. "And I think that all countries need to work together quickly so that this incident gets cleared up."

Skripal is a former Russian intelligence officer. He passed on information to British intelligence for years before eventually getting arrested in 2004. He was convicted for treason in 2006, but released to the United Kingdom as part of a spy swap in 2010 following a pardon by then-president of Russia, Dmitry Medvedev.

On Mar. 4 this year, Skripal and his daughter Yulia were found unconscious on a public bench in Salisbury in England. It was later determined that they were poisoned with a nerve agent. Several police officers working on the investigation were injured as well, and the British authorities declared a major incident, with several agencies working together to clarify what happened.