Customers wanting to open a US dollar account must provide proof of citizenship and residency to RBC, which has extensive bank and brokerage operations in the United States.
The Toronto-based company said in a statement: "RBC seeks to serve all of our clients to the best of our abilities, including helping qualified clients open a US dollar account."
RBC has defended its decision to impose tighter restrictions on US dollar accounts, which are designed to stop terrorist financing and money laundering and are in line with US government moves to tighten existing legislation.
The statement follows a recent television report on the issue by Radio-Canada revealing that citizens from a number of countries, including Myanmar, Iraq, Cuba, Iran, North Korea and Sudan, were being blocked from opening RBC US dollar accounts.
Citizens with dual nationality from sanctioned countries may be able to open accounts if they pass a series of stringent checks, including proof of residency in Canada.