EU foreign ministers are set to impose an embargo on Iranian oil to pressure the country to resume talks on its nuclear program.
The EU is also considered likely Monday to freeze the assets of the Iranian central bank.
"The pressure of sanctions is designed to try and make sure that Iran takes seriously our request to come to the table," EU foreign policy chief Catherine Ashton said on her way into the foreign ministers meeting in Brussels.
Iran says its nuclear program is exclusively for peaceful purposes. But many international officials fear the country is trying to develop nuclear weapons.
While an oil embargo is likely to be announced, diplomats say important details on how and when it would be implemented remain to be negotiated.
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