According to the premier, Russia's partial mobilisation of reserves require Finnish security authorities to reassess security threats.
"The assessment has to be done very quickly," Marin told reporters gathered at parliament.
Marin added that the government had heard the assessments of the situation from various ministries and authorities on Thursday.
Marin also commented on the situation regarding Russian tourist visas.
"We have to put an end to Russian travel and tourism, how to do this is a more complicated question," Marin said.
If the security situation at border crossings is assessed to have deteriorated, new solutions are possible to limit visas, for example restricting border crossings from Russia to Finland.
Finland has already sought to tighten restrictions on Russians leisure travelling in Finland and transiting to other countries.
Marin said during parliamentary question time on Thursday that the government is ready to take action to put an end to Russian tourism.
Yesterday in New York, Minister for Foreign Affairs, Pekka Haavisto (Green), said that Finland is preparing its own, national solution on tourist visas for Russians.
According to Yle, family visits will still be permissible under any new restrictions.