Finns Party chair Timo Soini says Finland is under no obligation to take part.
"The banks need capital, but it should come from Spain, Germany and France, who have created this mess. Finland should not have any part in this," Soini said on Sunday.
Sipilä harks back to 1990s
The new leader of the Centre Party, Juha Sipilä, says his party does not support funding large countries out of the eurozone's crisis fund. Sipilä, who was elected on Saturday just as Spain made its support request, argued that each country must take care of its own banking system.
In his address closing the Rovaniemi party congress on Sunday, Sipilä said: "Spain must rescue the Spanish banks. That is what Finland did during its banking crisis in the '90s."
He stressed that this did not yet mean that Finland should leave the common currency bloc.
"Now we should consider what alternatives we have if the euro begins to break up, because that is entirely possible," Sipilä added.