By Laura Trevelyan
BBC News, New York
Diplomats at the UN say they have made "substantial progress" in reaching a consensus on further sanctions against Iran over its nuclear activities.
Iran insists its nuclear programme is for peaceful purposes
However, Russia and China, which have strong commercial ties with Iran, are continuing to oppose any tough action.
But ambassadors from the five permanent members of the UN Security Council plus Germany emerged from a meeting on Monday to say agreement was close.
The measures are designed to tighten existing sanctions imposed in December.
Ambassadors admit privately that the nature of the sanctions being discussed is limited.
What is important, say Western diplomats, is to present a united front and show Iran there is disapproval at the UN over its uranium enrichment programme.
But getting agreement has not been that easy. Measures under discussion have included an arms embargo and stopping taxpayer-funded credits for companies that trade with Iran.
After the latest Security Council meeting, the British ambassador to the UN, Sir Emyr Jones Parry, said the aim was not to penalise anyone.
"We're trying to encourage, through this resolution, that good sense would prevail, that the government of Iran would accept what is on offer... and come back into negotiations," he said.
Mahmoud Ahmadinejad is seeking an audience at the UN
There have been disagreements, with Russia and China arguing that the scope of the measures is too broad and risk punishing Iran's people.
Both countries also have substantial trade links with Iran.
Germany has also argued that some of the measures could hurt its small businesses which trade with Iran.
Iranian TV has reported that President Mahmoud Ahmadinejad wants to address the UN's Security Council in person to explain Iran's nuclear programme, which he says is peaceful.
An obvious opportunity for him to do this could come when the Council votes on this resolution.