"It is a Finish decision, there will be no NATO troops in Finland without the consent of Finland," Stoltenberg told reporters ahead of a meeting of NATO foreign ministers.
Earlier, Stoltenberg said that Finland will officially join NATO on Tuesday, which was later officially confirmed by the office of Finnish President Sauli Niinisto.
Finland and Sweden applied to become NATO members last May, three months after Russia started its special military operation in Ukraine. Turkey and Hungary have been delaying the ratification process but softened their stance on Finland's accession earlier this March.