"Elections are no magic potion, but part of a political process," UN envoy al-Akhdar al-Ibrahimi, architect of the political process leading to elections in Iraq, told Dutch newspaper NRC Handelsblad in an article published on Saturday.
"They must be prepared well and take place at the right time to produce the good effects that you expect from them."
Asked if it was possible to hold elections as conditions exist now, al-Ibrahimi said: "If the circumstances stay as they are, I personally don't think so."
"It is a mess in Iraq," al-Ibrahimi said. "The international community, hopefully together with the Americans, must help the Iraqis to clean up this mess. If you let it deteriorate, the situation will become even more dangerous."
In the latest strike against Iraq's shaky security forces, twin car bombs blew up outside a police station near Baghdad's Green Zone on Saturday, killing at least three people and wounding more than 40.
Many Iraqi Sunnis have called for a delay in the elections, saying that violence in Sunni areas will prevent the polls being free and fair.
Sunni Arabs, who dominated Iraq during Saddam Hussein's rule, fear they will be marginalised in the new Iraq, as the Shia exercises new-found political clout.
The Shia insist the elections should go ahead on time, arguing that any delay would be a "surrender to terrorism". Iraq's Kurds in the north say they are ready for elections, but would accept a delay if others wanted it.