The chair of parliament's Foreign Affairs Committee, Mika Niikko (Finns), was forced to explain his comments on Twitter that appeared to contradict Finland's foreign policy positions.
He had suggested that French President Emmanuel Macron, or someone else, should state publicly that Ukraine would not join Nato.
He soon deleted the tweet, which suggested that Russia would not regard this week's visit to Moscow by Macron as a success unless such a statement was forthcoming.
Niikko then told Yle that he supported Ukraine's sovereignty, and had worded his tweet carelessly.
"The goal was not to take a position on whether Ukraine could seek Nato membership," said Niikko. "Ukraine is fully entitled to make its own decisions."
The Finns Party MP was criticised heavily on Twitter for his original tweet.
"Finland's position is clear and has been restated regularly," said Centre MP Joonas Könttä. "All independent states have the right to decide on their own security. It is not Finland's place to advise on how other states should make those decisions."
Niikko said that he had wanted to put forward his own view that Ukrainian Nato membership is not currently a realistic prospect.
"Everyone knows that Ukraine and Nato decide on possible membership applications themselves, nobody else has a say," said Niikko. "It is not about a move in a certain direction, my comment was acknowledging the reality that in this situation, Nato is not going to save Ukraine. That is my personal opinion."
"Finland's foreign policy line is that we give full support for Ukrainian sovereignty."
Niikko has previously been forced to explain his stake in a firm funded by the Chinese state, a company he had lobbied for. Neither he nor his Finns Party colleague Ville Vähämäki had declared their stakes in the firm.
Niikko was allowed to retain his position as chair of the committee after MPs deliberated on the matter.