Iran said it could endorse a U.N. deal for it to send potential nuclear fuel abroad for processing.
An al Qaeda-linked group has said it carried out the twin suicide bombings that killed 155 people in Baghdad on Sunday.
Iraqis think political infighting before next year's election is the cause and fear worse is yet to come.
The death toll from Sunday's Baghdad suicide bombs, one of Iraq 's bloodiest attacks in years, has risen to 155.
Two suicide bombs tore through Baghdad on Sunday, killing 132 people.
Tunisians voted on Sunday in an election almost certain to extend the rule of President Zine al-Abidine Ben Ali.
Afghanistan will hardly have enough time to provide full security during a presidential election run-off in November.
Fifteen members of Iran's Revolutionary Guards were among those killed in Sunday's suicide bombing.
Iran demanded that the U.N. Security Council condemn a bomb attack last weekend that killed dozens of people.
Afghan President Karzai, under intense international pressure, is likely to announce he is ready for a run-off.