United Nations envoy Kofi Annan has warned that failing to resolve the crisis in Syria could bring unimaginable consequences.

He spoke Tuesday after talks with Iranian Foreign Minister Ali Akbar Salehi in Tehran as part of an effort to rescue his peace plan for Syria. Iran is Syria's top ally in the region.

Mr. Annan said the Iranian government has cooperated with his efforts and he looks forward to continuing to work with Tehran toward a peaceful solution.

“If we do not make a real effort to resolve this issue peacefully, and it were to get out of hand and spread to the region, it can lead to consequences that none of us could imagine.”

Mr. Annan is now in Baghdad to discuss the Syrian crisis with Iraqi Prime Minister Nouri al-Maliki.

In Russia, Interfax news agency reports that Russian ships from northern fleets will coordinate with a unit of Black Sea warships for combat training in the Mediterranean and Black seas. Other reports say at least one ship will head for Syria.

Western nations have criticized Russia for failing to cut military ties with Syria. On Monday, a senior Russian defense official said Moscow will not sell more weapons to Syria until the situation there calms down.