Progress in talks aimed at reviving the 2015 Iran nuclear accord has not included subjects at the heart of the negotiation, a French diplomatic source said on Thursday, adding that there needed a change of approach ahead of a decisive February.
Indirect talks between Iran and the US on salvaging the nuclear deal resumed almost two months ago.
Western diplomats have previously indicated they were hoping to have a breakthrough over the next few weeks, but sharp differences remain with the toughest issues still unresolved. Iran has rejected any deadline imposed by Western powers.
“There is partial, timid and slow progress on the subjects which are not the subjects at the heart of the negotiation which we know are the most important,” the source told reporters on condition of anonymity after ministers from Britain, France, Germany and the US met in Berlin.
“We will not be able to do it (return to the deal) if Iran continues on this trajectory at nuclear level and if the negotiation proceeds in the same way.”
The eighth round of talks, the first under Iran's new hard-line President Ebrahim Raisi, resumed after adding some new Iranian demands to a working text.
Iran refuses to directly meet US officials, meaning that other parties -- Britain, China, France, Germany and Russia -- must shuttle between the two sides.
The source would not set a deadline, but said the current trend was untenable.
“It seems necessary to us to change approach. I think that the month of February will be absolutely decisive. We are not going to continue like this in Vienna on the current trajectories in March, April, May etc.”