The U.S. military has bolstered its presence across the Middle East amid escalating tensions with Iran, as nuclear talks were thrown into uncertainty Wednesday before being moved to Oman. U.S. and Iranian officials had been expected to meet Friday in Istanbul,

Iran and the United States started high-stakes negotiations via Omani mediation to try to overcome sharp differences over Tehran's nuclear programme, while a dispute over widening the agenda risked derailing diplomacy and triggering another Middle East conflict.

Iran and the United States stood poised Friday to hold negotiations in Oman at least over Tehran’s nuclear program after a chaotic week that initially saw plans for regional countries to take part in talks in Turkey.

ABC News' Ian Pannell and contributor Mick Mulroy discuss what's at stake in talks between the two countries about Tehran's nuclear program.

Iran’s Foreign Minister Abbas Araghchi has confirmed that Iran and the United States will hold nuclear talks in Oman’s capital, Muscat, on Friday

The chief of Central Command is set to join the talks, as the U.S. builds up military forces ahead of a possible strike.

The US has built up its military presence in the Middle East in response to Iran's violent crackdown on protests.

The United States and Iran will hold talks Friday in Oman as the two hope to iron out their differences on nuclear capabilities and more.