The former Finnish president told Finnish commercial broadcaster MTV3 on Friday evening that there would be no point in trying to act without a clear mandate from the Council.
Ahtisaari has mediated in peace talks in Aceh, Namibia and Kosovo.
FM: Observers play a key role
Interviewed earlier by Yle, Foreign Minister Erkki Tuomioja expressed the hope that the UN peacekeepers can remain in Syria.
"Although they are not able to carry out their original mission since there is no peace in the country," says Tuomioja, "still, at the moment the observers' presence has produced information and allowed quicker reporting on what is actually happening and evaluations of who is responsible for various massacres, for instance."
Haavisto: Finland has a responsibility
Also on Friday, former EU Envoy to Sudan and presidential candidate Pekka Haavisto criticised the UN Security Council and the international community in general for its handling of the Syrian crisis.
In a blog posting, the Greens MP notes that the international community has not been able to put pressure on Syrian President Bashar al-Assad's regime because the Council has been unable to agree on sanctions.
Haavisto said the situation is desperate following Kofi Annan's abandonment of his peace efforts. He added that as Finland is seeking a seat on the Security Council, it must also help to reach an internationally-approved solution to the crisis.
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Allotment gardens bring community spirit
Spring brings many citydwellers to community gardens – including growing numbers of immigrants.
Starbucks to open in landmark Aalto building?
The world’s largest coffeeshop chain plans to open its first non-airport café in Finland at Helsinki’s Academic Bookshop, Yle has learned.
Valio recalls salad mix over datura fears
A second food product has been withdrawn in Finland because of a risk that it could contain poisonous seeds.
Five-vehicle crash near Kotka kills two
Part of Highway 7 remained closed for more than five hours after the collision.
Swine flu shots boosted adult risk of narcolepsy, too
The national health agency has confirmed that kids weren't the only ones with an elevated risk following the H1N1 jab a few years ago.
Nine people now affected by datura poisoning
Nine people have now been affected by datura contamination from frozen vegetables sold by a Finnish supermarket. Most symptoms are mild, with dry mouth, a quickening pulse and weakened vision the main effects, but some people have required hospital treatment.
Finland criticised again in Amnesty report
The human rights organisation’s annual report is highly critical of Finland’s treatment of asylum seekers. Finland was condemned for deporting asylum seekers without in-country appeals, and the practice of incarcerating children seeking refugee status in police facilities.
FFE: One in four businesses made a loss in 2012
A quarter of all Finnish firms lost money last year, according to the in-house magazine published by the Federation of Finnish Enterprises (FFE).
Baby boomers' alcohol "time bomb" set to hit Finland
Experts fear that retiring baby boomers may over indulge to such an extent that Finland could soon be forced to deal with a large cohort with unusually high levels of alcohol dependence. Incorporating messages about alcohol into basic healthcare will be key to fighting the problem.
Finnish income gap lower than European average
Income differences in Finland are below the average in Europe, according to Statistics Finland. The gap between richest and poorest is largest in Latvia and Bulgaria and smallest in Norway and Iceland.