The United Nations Security Council has agreed on a resolution to impose a new round of sanctions on Iran over its nuclear program.
The council's five permanent members - Britain, France, China, Russia and the United States - are co-sponsoring the sanctions draft and believe they have the votes to secure its passage.
The resolution tightens financial restrictions, toughens shipping inspections and expands a limited arms embargo.
The timing of the vote depends on an agreement of annexes, listing individuals and entities subject to asset freezes and travel bans.
Diplomats say that could happen as early as Wednesday, and there is little doubt the resolution will be adopted.
A number of nations could abstain or vote against it, but none of them have veto powers.
Iranian president Mahmoud Ahmadinejad says he will reject talks to resolve the nuclear impasse if new sanctions are imposed.
"I have said the US government and its allies are mistaken if they think they can brandish the stick of resolution and then sit down to talk with us. Such a thing will not happen," he said.
"We will talk to everyone if there is respect and fairness, but if someone wants to talk to us rudely and in a domineering manner the response is known already."
Mr Ahmadinejad, who is in Turkey for the summit of an Asian security grouping, urged Western powers not to dismiss a nuclear fuel swap deal brokered by Turkey and Brazil last month.
Meanwhile, Russia will establish a joint venture with Iran to operate Tehran's first nuclear plant.
Chief of Russia's nuclear state corporation, Sergei Kiriyenko, said the project is set to come online in the coming months.
Russia has been helping Iran build its first nuclear plant in the southern city of Bushehr since the mid-1990s, but its launch has been marred by a series of delays.