Riyadh [Saudi Arabia], June 26 (ANI): As Tehran and Washington continue with their engagements following the signing of the MoU earlier this month, sources have told Al Arabiya that the two are set to hold the next round of negotiations in Switzerland on June 28 and 29. Citing sources, Al Arabiya said that the next round of US-Iran negotiations will be held on June 28 and 29 at the Burgenstock resort in Switzerl