The office of EU foreign policy chief Catherine Ashton confirmed Iran and six world powers would hold their first negotiating round since they failed to meet a July 20 target date for an agreement in New York on September 18.
The deadline was extended until November 24 after six months of talks because wide gaps persisted over the future scope of Iran's uranium enrichment programme, which can have both civilian and military applications.
The six powers - the US, Russia, China, France, Germany and Britain - aim to persuade Iran to scale back its nuclear programme in exchange for phasing out sanctions that have severely hurt its oil-dependent economy.
The election last year of President Hassan Rouhani, widely seen as a pragmatist, raised hopes of a settlement of the standoff after years of soaring tension and fears of a new Middle East war, and an interim accord was reached between Iran and the six powers in Geneva late last year.
But Western diplomats say the sides remain far apart on what a final deal should look like - especially on the issue of how many enrichment centrifuges Iran can operate.