A total of 112 MPs responded to Yle's most recent questionnaire, with 71 saying they were in favour of Finland applying to join Nato while just six were opposed.
According to chair Riikka Purra, members of the parliamentary group will be allowed to vote their conscience in a possible parliamentary decision on Nato.
A total of 122 MPs replied to Yle's survey, with 70 saying they were in favour of the move and 33 against. Some 19 MPs were unwilling to reveal their position.
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