44 CFR § 402.4 - Calls at restricted ports en route to an unrestricted port with restricted cargo.
Order T-1 does not prohibit an American flag ship or aircraft from going to or calling at one of the restricted ports, even though it has on board a commodity which could not be discharged at that port. (Note, however, that Order T-2 prohibits American flag ships and aircraft from calling at any port or other place in Communist China.) For example, an American flag ship may call at one of the restricted ports (except one in Communist China), even though it has on board the following classes of commodities:
(a) A Positive List commodity manifested to a destination outside the restricted area, with an export license and an export declaration showing the unrestricted destination at the ultimate destination, (b) a Positive List commodity destined for the restricted port of call which cannot be discharged there because there is no export license or authorization from the Assistant Secretary for Domestic and International Business permitting discharge at the restricted port of call, (c) a commodity of any kind destined for Communist China (the transportation and discharge of which is covered by Order T-2). None of these commodities may be discharged at the restricted port of call. Discharge of any of these commodities at the port covered by the restrictions of Order T-1 is prohibited and subject to penalty, regardless of the circumstances under which the discharge of the cargo at the restricted port occurs, unless appropriate authorization is obtained.