Iranian and European foreign ministers have agreed to resume negotiations next week regarding Iran's nuclear program and related sanctions, following heightened tensions and threats to re-activate United Nations penalties. The European powers have warned Iran that unless a verifiable and lasting agreement is reached to address concerns over uranium enrichment, sanctions could quickly be reinstated. Iranian officials, meanwhile, have challenged the legitimacy of such actions and cautioned about their consequences. Recent talks have stalled amid conflict and restricted access for international inspectors, but a new round of discussions is set to take place in Vienna with hopes of breaking the deadlock.