Papandreou, who is also president of the Socialist International, had been scheduled to meet with the leader of the Finnish Social Democratic party but, due to illness of the latter, met instead with the leader of the party's parliamentary group.
"It is crucial for Europe to take important decisions," Papan-dreou said on Wednesday in a joint press conference with Kiviniemi, adding that "these decisions we will take will be very crucial and historic for all of Europe, the eurozone and the euro currency."
Papandreou said that important and comprehensive "package decisions" must be taken in March so that stability may return to the markets, while he also underlined the major reforms being made in Greece.
"The (EU-IMF support) loan (to Greece) will be repaid, with interest," Papandreou stressed, adding that the Finnish taxpayers "have no need to worry".
On the extension of the repayment period for the Greek loan, Kiviniemi said that Finland is prepared to contribute to the establishment of a comprehensive package that will calm the markets, adding that if corresponding situations arose with other countries facing difficulties, such as Greece, the solution will be provided through that package.
She further expressed her country's satisfaction with the measures that were taken immediately by Greece to balance the economy, but added that the situation remained fragile and that "more painful reforms are still on the way".
"We anticipate that Greece will continue to institute tough structural reforms over the coming months," Kiviniemi said, adding that this was necessary not only for Greece's future but for the future of Europe as a whole.
"It is the best way to ensure the economic stability and prosperity of our citizens," she added.
Responding to press questions, Kiviniemi said that Finland was closely monitoring the evaluations of Greece by the EU and the IMF and, "up to now, the results have been good, but of course continuation of the reforms is of great importance", adding that "there is much more to be done".
Papandreou, in turn, said that Greece is committed to rendering the country's economy viable and credible to the European Union, its partners and its lenders. "We are credible and we will repay the loan with interest," he stressed.
He said that re-examination and reinforcement of the rules "for our greatest achievement, economic union", is necessary in order to create stability in the markets "because we saw great fear and nervousness regarding Greece but also other countries, and in general over the euro".
"This means that important and comprehensive package solutions need to be taken in March, and naturally Finland has played a key role in those," Papandreou noted.
Although such decisions are difficult and complex, "we are capable of taking the decisions and securing the support of our peoples and ensuring that the euro will continue to be strong and stable, of stabilising our economies and of making Europe competitive at global level", the Greek premier stressed.
"The bottom line is that we are called on to take decisions in accordance with the interests of our countries and citizens, because we are members of a Union, of a common family of values, we have a common currency, a common political and economic Union," he pointed out.
Asked if he believed that the EU member states will allow Greece to "re-program" its loans, giving it more time, and if he can guarantee that this would not entail a risk for the Finnish taxpayers, Papandreou stressed that one of the reasons that the reforms are being made is to make the economy viable and so that "we will have the ability to repay our debt".
"I can guarantee that the loan will be repaid, with interest, and that the Finnish taxpayers need not worry," Papandreou added.
He further said that 80 percent of the more difficult decisions have already been taken by Greece, noting that more still needs to be done with respect to transparency, e-governance, public administration, education, the agricultural model and tourism, adding that "we want to take advantage of the state assets, bring investments, be able to denationalise in order to help us reduce the state debt, in tandem with boosting growth".
"We aim to become the Finland of the South, to the degree possible," he said, responding to a reference by Kiviniemi, and noted that Greece was working closely with Finland in various sectors such as education, adding that other fields of cooperation were also discussed.
He also outlined the changes that have been made in Greece in just one year, adding that they will continue, having ensured the time required through the support mechanism on which "we collectively took important decisions".
Papandreou further thanked the Finnish government and people for their support to Greece.
On the developments in Egypt and Libya, Papandreou stressed that "we condemn violence" and that "we need a peaceful transition to democracy".
He also said that Europe, like Greece, has an important role to play, adding that Greece was currently taking part in the operation to evacuate citizens of third countries from Libya.