The Estonian post office Omniva released a new stamp design commemorating Finland's Nato membership on Friday, according to the Estonian public broadcaster ERR.
Newspaper Helsingin Sanomat reported that Estonia unveiled the stamp during a presentation at the Finnish Embassy in Tallinn.
"Finland's accession to NATO is a historic event and the stamp is our symbolic sign of support for the Finnish people to mark this very important moment," said Omniva's chair Mart Mägi.
The stamp's designer, Jaan Saar, chose white and blue as the main colours, mirroring those of the Finnish flag.
Estonia has been one of Finland's most vocal advocates during the country's nearly year-long Nato membership bid. Finland and Estonia also share historic, cultural and linguistic ties.
Finland joined Nato on 4 April earlier this year following a nearly 11 month-long application process triggered by Russia's invasion of Ukraine in 2022.
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