Finland's President Sauli Niinistö and Prime Minister Sanna Marin (SDP) have issued statements condemning Russia's plans to formally annex four Ukrainian regions.
Writing on Twitter, Niinistö said that Finland will "not recognise the results of the illegal referenda or annexations".
"Ukraine's sovereignty and territory is indivisible and inviolable," Niinistö wrote.
PM Marin meanwhile tweeted that "Russia's illegal sham referenda will never be recognised".
Russian President Vladimir Putin is expected to hold a signing ceremony on Friday afternoon, where four Russian-occupied regions of Ukraine – Luhansk and Donetsk in the east, and Zaporizhzhia and Kherson in the south — will be formally annexed.
This follows the holding of "referendums", which have been widely condemned by Ukraine and Western countries as a sham.
The BBC reports (siirryt toiseen palveluun) that a celebration and concert is scheduled to take place near the Red Square in central Moscow on Friday evening, noting that there have been reports people are being paid to attend the event.
This week's episode of All Points North explores the security considerations following Finland's decision to restrict the entry of Russian tourists. You can listen to the full podcast using the embedded player here, via Yle Areena, on Spotify or via the options found in this article.