European Union heads of state or government meet Thursday and Friday in Brussels to discuss the latest developments in financial markets and the economic and financial crisis.
But EU President Herman Van Rompuy said in his invitation letter that the 27 leaders will also "briefly" exchange views on the situation in Iran.
European nations, many of which pulled their ambassadors from Tehran, last week expressed "serious and deepening concerns" about Iran's nuclear program and said they would impose new sanctions, including freezing assets and a travel ban on 180 Iranian individuals and companies linked to Iran's nuclear program.
However, the EU fell short of agreeing to boycott Iran's oil sector. France led the push for the sanctions, backed by the Britain, but other countries, above all Greece, which rely on Iranian oil and face tough economic times, resisted the measure.
But EU foreign policy chief Catherine Ashton said an oil embargo was still "being debated" and German EU Energy Commissioner Guenther Oettinger told journalists on Tuesday that there is consensus among European Union states on the need for such a ban.
"I think an oil ban is an important instrument but we should integrate into this policy all other big countries, the US of course, Russia, the more the better," he said.
France and Britain will use the European Summit this week to push forward their plan to approve a full embargo on oil imports from Iran.
A EU ban on Iranian oil imports would be a significant blow to the Iranian economy and is meant to force the regime to think harder about its nuclear programme, EU diplomats were quoted as saying. Iran exports some 18 per cent of its oil to the EU.
If the EU approves an embargo, it will be one of the most significant measures imposed by western states who have expressed growing concern that Iran is seeking to build nuclear weapons.