What are the roles of banks in international trade?

In our days the bank have many roles in the operation of international trade with using of course the new technology of information : Trade facilitation (all the the operation will be in the first step and in the last related to the bank we can say that the bank is one of the importatnt actor in the foreign trade operation), insurance , follow-up the marchandise between importer and exporter and to finance the exportation or importation and that can help to development of business competetiveness

In a very brief wording, "banks are facilitate the international trade", through:

1- Mitigating related risks for the parts concerns ( i.e. the importers and the exporters).

2- Effecting payments / transferring funds related to international trade transactions.

3- Allowing sort of facilities to international trade concerned parts (Importers and Exporters). 

Bank are now very instrumental in supporting TRADE FINANCE activity in INTERNATIONAL TRADE as most of the  COMMERCIAL part of INTERNATIONAL TRADE needs support from BANK , whether there roles are defined as under : 

1. Advance T/T ., SWIFT , DD  ( payment route through bank ) 

2. Banks role is TRADE COLLECTION route ( DA & DP )  

3. Documentary Letter of Credit which by far provides the best payment route for International Trade payments