Iran nuclear talks extended; Russia says 'key aspects' agreed

Six world powers and Iran will meet again later on Wednesday in a bid to reach an outline accord reining in Tehran's nuclear programme, after failing to agree crucial details such as the lifting of U.N. sanctions by a Tuesday deadline.
   
The negotiators ended talks in the Swiss city of Lausanne in the early hours of Wednesday and said they would reconvene later in the day, with Iran and Russia expressing optimism that an initial agreement was within reach.
   
The preliminary deal would be a major milestone toward a final accord, with an end-June deadline, that could end a 12-year standoff and reduce the risk of another Middle East war.
   
With Iran asserting its "nuclear rights" and the United States threatening on Tuesday to abandon the negotiations, the talks have been bogged down on the issues of nuclear research, the lifting of U.N. sanctions and their restoration if Iran breaches the agreement.
   
Russian Foreign Minister Sergei Lavrov said negotiators had reached a general accord on "all key aspects", according to Russia's TASS news agency, while his Iranian counterpart said a draft agreement could be prepared on Wednesday.
   
But a diplomat close to the talks denied that such an agreement had been reached, and a French official said Foreign Minister Laurent Fabius was leaving the talks and would return from France when it was "useful". It was not clear whether his departure was a sign of a major problem in the talks.
  
The six powers - the United States, Britain, France, Germany, Russia and China - aim to stop Iran from gaining the capacity to develop a nuclear bomb in exchange for easing international sanctions that are crippling its economy.
   
Iran says its nuclear programme is...