US Showing 'Constructive, Amicable' Attitude in Work Contacts With Russia - Kremlin Aide

"We have work underway at the expert level. Ours are constantly working on the documents for the upcoming summit. That is, everything is proceeding as usual," Ushakov told Russian media.

The G20 summit will be held in Miami on December 14-15. Kremlin spokesman Dmitry Peskov told journalists in late July that Russia would take part in the event.

"Well, I would say yes, the situation around Iran is causing some friction among a number of participants. I think we will reach consensus, it seems to me," Ushakov said, speaking about whether the wording "war against Iran" is the central issue in coordinating the declaration.