It's not enforced but it's a de facto practical requirement.
If Polbank (forgive me for the bastardized names) wants to give 1M USD to Bankpolska, they either need to ship cash (which can be done but is expensive or tricky) or have a specific bilateral agreement betwene them (which can be done and is done sometimes, but linking every bank with every other bank bilaterally does not scale), or need some interbank settlement system that will do that, but there's no such system in which they can participate. E.g. there's Fedwire but neither Polbank or Bankpolska can be direct members as far as I understand (they generally are not members; I'm not certain if it's caused by some strict limitation or just practicalities and costs.)
So the standard means is to use 'correspondent banks' e.g. USA banks that do that for them. Polbank might have an USD account with Chase or Citi, and Polbank can ask Chase (via a SWIFT message usually) "hey transfer $1m from our account to Bankpolska, it's cover for a customer deal #1234" - but this means that the transaction "goes through" USA.
Alternatively, multinational banks may have branches in both USA and Poland and so they can be direct participants and settle this directly, however, then it would involve a Fedwire transfer (in USA, subject to USA laws and limitations) between Polbank USA branch and Bankpolska USA branch.
That's standard practice for pretty much every currency. EUR settlement between two American banks usually (not always, there are various options) goes through EU, RUB settlement usually goes through Russia, etc.
If there's a sufficient need, Polish banks could establish an interbank settlement system through which they could transfer USD directly (e.g. similar to the one they have for transfering Polish zloty), but it's a hassle and has costs, so currently they have not done so because for them it's generally not a problem to route all USD payments through USA.
There have occasionally been efforts to do large international USD transactions which don't touch the US, usually because one or both of the participants is under US sanction. There is enough USD infrastructure in London that it may be an alternative to New York, but everyone involved has to scrupulously avoid any interaction with any machinery under US jurisdiction, which is quite difficult.
I learned about this from reading the case brought in he UK by the US government to try to stop this happening. I didn't bookmark it, and of course can't find it now.
Not this, but an example of how it can go wrong:
> According to the settlement agreement, BACB actively solicited U.S. dollar business from Sudanese banks and processed the transactions by way of an internal book transfer process that involved a nostro account maintained at a foreign bank (Bank B) located in a country that imports Sudanese-origin oil. (A nostro account is an account a bank holds in a foreign currency in another bank.) Although these transactions were not processed to or through the U.S. financial system, the process to fund BACB’s U.S. dollar nostro account at the foreign bank did involve transactions processed by or through U.S financial institutions in apparent violation of the U.S. economic sanctions.
> If there's a sufficient need, Polish banks could establish an interbank settlement system through which they could transfer USD directly (e.g. similar to the one they have for transfering Polish zloty), but it's a hassle and has costs, so currently they have not done so because for them it's generally not a problem to route all USD payments through USA.
Doesn't it still need to be involved with USA? I mean, sure, they can use this settlement system to trade between each other independent of Fed, but ultimately the funds in the settlement system have to be stored as reserves in Fed, i.e. in some bank under US jurisdiction. So, after all, US still has control over this new settlement system, but now they can't freeze individual accounts in it, they can only freeze funds in reserve account(s) that this system consist of, potentially affecting many (innocent) parties. Am I right?
Euro dollars are constantly traded without going through the US.
CLS currencies and any currency which is fully convertible can be used in transactions without any involvement of the jurisdiction that minted the currency in the first place.
The USD has a huge settlement infrastructure that is completely independent of the US.
Doesn't it still involve accounts in US banks though? Please see my direct reply PeterisP for explanation. I cannot see how could it work without Fed oversight as it would allow it to "print" dollars.
Also, could you please share more info? I'm very interested in financial settlement system, especially for USD and EUR, but sadly there's too little public resources.
If Polbank (forgive me for the bastardized names) wants to give 1M USD to Bankpolska, they either need to ship cash (which can be done but is expensive or tricky) or have a specific bilateral agreement betwene them (which can be done and is done sometimes, but linking every bank with every other bank bilaterally does not scale), or need some interbank settlement system that will do that, but there's no such system in which they can participate. E.g. there's Fedwire but neither Polbank or Bankpolska can be direct members as far as I understand (they generally are not members; I'm not certain if it's caused by some strict limitation or just practicalities and costs.)
So the standard means is to use 'correspondent banks' e.g. USA banks that do that for them. Polbank might have an USD account with Chase or Citi, and Polbank can ask Chase (via a SWIFT message usually) "hey transfer $1m from our account to Bankpolska, it's cover for a customer deal #1234" - but this means that the transaction "goes through" USA.
Alternatively, multinational banks may have branches in both USA and Poland and so they can be direct participants and settle this directly, however, then it would involve a Fedwire transfer (in USA, subject to USA laws and limitations) between Polbank USA branch and Bankpolska USA branch.
That's standard practice for pretty much every currency. EUR settlement between two American banks usually (not always, there are various options) goes through EU, RUB settlement usually goes through Russia, etc.
If there's a sufficient need, Polish banks could establish an interbank settlement system through which they could transfer USD directly (e.g. similar to the one they have for transfering Polish zloty), but it's a hassle and has costs, so currently they have not done so because for them it's generally not a problem to route all USD payments through USA.