VIENNA, Nov 9: Iran must tell the United Nations nuclear watchdog in writing that it will suspend its uranium enrichment programme from a specific date to help it avoid sanctions , western diplomats said on Tuesday.

France, Britain and Germany reached a tentative accord with Tehran on freezing enrichment activities during talks in Paris over the weekend. The formal announcement to this effect is likely to be made on Wednesday.

"Iran needs to send a letter to the (International Atomic Energy Agency) stating that it will suspend enrichment on such-and-such a date," a western diplomat who follows the IAEA in Vienna told Reuters.

"Iran has been told that the IAEA needs this letter by tomorrow (Wednesday) if it is going to be in the report," the diplomat said, referring to IAEA chief Mohamed ElBaradei's progress report on Iran inspections.

Several Vienna-based diplomats said Mr ElBaradei had promised Tehran a positive report if talks between the European Union's 'big three' states aimed at freezing Iran's uranium enrichment programme went well.

The combination of a positive IAEA report and verified suspension of all activities related to uranium enrichment and a process of purifying fuel for use in nuclear power plants or weapons will guarantee that Iran would escape a referral to the UN Security Council this month, diplomats say.

It would also give British Prime Minister Tony Blair a positive message to take to talks with President George W. Bush on Thursday and Friday. That would strengthen Europe's hand in urging the United States to engage with Iran.

Washington wants Tehran reported to the UN Security Council for hiding its enrichment programme for 18 years.-Reuters