Finnish MPs on Tuesday approved the decision to apply for membership in the North Atlantic Treaty Organisation (Nato) in a vote of 188 in favour to 8 against.
Three MPs were marked as absent in the vote.
On Sunday, President Sauli Niinistö and Prime Minister Sanna Marin (SDP) announced that Finland will seek to join the Nato alliance. The issue then moved to Parliament for a lengthy debate that began on Monday and a subsequent vote.
Parliament's approval means that the president and government are now able to put the official application process into motion, possibly as soon as later on Tuesday.
The vote was required after Left Alliance MP Markus Mustajärvi tabled a counter-motion, arguing that Finland should remain militarily non-aligned. His motion was backed by party colleagues Johannes Yrttiaho and Katja Hänninen.
A total of 212 speeches were made to Parliament during the 14-hour plenary session that preceded the vote.
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