Iran says it will resume technical talks with six world powers in Geneva on Thursday and Friday, a vital step in implementing a deal signed last month which suspends key elements of Tehran's nuclear programme in exchange for limited relief from sanctions.

The talks between expert teams may continue into Saturday and Sunday if required, Fars news agency reported Iran's deputy chief negotiator, Abbas Araqchi, as saying.

Last Thursday Iranian negotiators interrupted technical talks in Vienna in protest against the US blacklisting of an additional 19 Iranian companies and individuals under existing sanctions, saying the move was against the spirit of the nuclear deal.

US officials maintain the blacklisting does not violate the Nov. 24 agreement and say they gave Iran advance warning of the action.

The development has highlighted the sensitivities involved in implementing the agreement. Some US lawmakers are pushing for further sanctions against Iran, a move which hardliners in Iran see as proof the United States cannot be trusted.

The six powers - the United States, Russia, China, Britain, France and Germany - are seeking to curb Iran's atomic programme to prevent it from acquiring nuclear weapons. Iran denies any such intention, saying it needs nuclear power in order to generate electricity.