A top adviser to Supreme Leader Ayatollah Ali Khamenei said Thursday Iran will not yield to U.S. threats over a ballistic missile test. Iran said Wednesday it had tested a new ballistic missile but said it did not breach a nuclear deal reached with six major powers in 2015 or a U.N. Security...

Ukrainian President Petro Poroshenko vowed Thursday to hold a referendum on NATO membership amid renewed tensions with Russia. "As the president, I act in accordance with the views of my people, and I will hold a referendum on the question of NATO membership," Poroshenko said in an interview...

Russian plane maker Sukhoi has repaired defects in 20 Superjet 100 aircraft that were grounded in December by airlines including Russia's Aeroflot and Mexico's Interjet, the company said Thursday. Checks by Russia's aviation authority were instigated in late December after a defect was...

U.S. Defense Secretary Jim Mattis said he would sound out ally South Korea on efforts to address North Korea's nuclear and missile programs as he arrived in Seoul Thursday, including plans to deploy a U.S. missile defense system there. Mattis' visit comes amid concern that the North may be...