Six world powers are meeting in Brussels later on November 21 for talks on Iran's controversial nuclear program.
Officials from Britain, China, France, Germany, Russia and the United States will discuss plans to hold a fresh round of talks with Tehran.
Three rounds of negotiations thus far this year have not led to any breakthrough. Iran denies Western charges it is pursuing nuclear weapons, and has refused to halt uranium enrichment, as dictated by UN Security Council resolutions.
Sanctions pressure increased last month when European Union governments stepped up restrictions on trading with Tehran and banned imports of Iranian gas, adding to an embargo this year on Iran's crude oil.
A UN report showed this month Iran is set to sharply expand uranium enrichment in its underground Fordow plant.
Based on AFP and Reuters reporting