"I call on the conscience of all religious and political leaders not to let anger win over peace, and to use their wisdom, because the country is at a crossroads," Martin Kobler said in a statement on Friday.
Kobler was speaking a day after Prime Minister Nuri al-Maliki warned of attempts to return Iraq to "sectarian civil war".
In a Thursday televised speech, Maliki called on everyone worried about Iraq's future "to take the initiative, and not be silent about those who want to take the country back to sectarian civil war."
The comments come as a bloody four-day wave of violence, including multiple attacks at mosques, killed 195 people in Iraq.
The unrests which many believe are being orchestrated from outside the country were the deadliest so far linked to demonstrations that erupted more than four months ago.
Some analysts suspect a role of United States in fueling the flames of violence in Iraq to avert attentions from what they are conspiring in Syria crisis.
Carol Turner, a British political expert told Al-Alam on Friday that in the last two years the US and western countries have been trying to not only fuel the war in Syria but also spread it to other countries in the Middle East so that they could exploit the insecurities and unrests to their own benefits.
She said the US and its allies are suffering a defeat in Syria, as they haven’t been able to get what they sought, and so they try to make another conflict in the region to cover-up their failures.