You keep talking about relationships, the problem is the people change on a regular basis making barter between nations impractical if not impossible.
Bartering is maybe not the best word but it speaks well.
And yes, countries do have relationships. short and long term and constantly changing.
Countries do have relationships, but they trade in currency.
Putin has options to trade, like I said earlier, they have China and the other BRICS countries and establish another from of trade without the SWIFT system.