The United States and Iran are due to hold their second round of nuclear talks on Saturday, as what both sides are looking for in a deal begins to take shape.

Oman's Sultan Haitham bin Tariq al-Said is set to visit Moscow on Monday, days after the start of a round of Muscat-mediated nuclear talks between the U.S. and Iran. The sultan will hold talks with Russian President Vladimir Putin on Tuesday,

That the talks are even happening represents a historic moment, given the decades of enmity between the two countries since the 1979 Islamic Revolution and the U.S. Embassy hostage crisis.