GENEVA/BRUSSELS - Iran and six world powers began expert-level talks in Geneva on Thursday to work out how to put into practice a landmark deal obliging Tehran to curb its nuclear programme in return for some relief from economic sanctions.
Discussions on the details of last month's breakthrough accord were interrupted by Tehran diplomats last week, after a decision by the United States to blacklist 19 more Iranian companies and individuals.
But diplomats said much progress had been achieved in the four-day meeting on Dec. 9-12 in Vienna, and expressed hope they could wrap up the practical discussions at meetings in Geneva on Thursday and Friday.
That could mean the seven countries - the United States, Russia, China, France, Britain, Germany and Iran - would be ready to agree on a date when the accord goes into effect.
Specifically, they would decide when western governments lift some economic sanctions and Iran curbs its most sensitive nuclear work.
"We were at an advanced stage in Vienna," said a diplomat from one of the six world powers. "A lot of work has been done so we can go very fast."
The diplomat, who spoke on condition of anonymity, cautioned, however, that some western diplomats were concerned Iran could be "more difficult" in the technical discussions because of Washington's decision to expand sanctions this month.