What is the master of a UK ship expected to do if a foreign port or another ship it is interfacing with does not meet ISPS Code security requirements?

It will ultimately be a commercial decision for the UK ship as to whether it calls at its intended destination or goes alongside the other ship.

Where it is decided that the UK ship will call at a port that does not meet ISPS Code security requirements, the master should request a Declaration of Security, in order to ensure that the ship is not prejudiced against at future ports of call.