This is reported by the Associated Press.
As noted, Pyongyang often condemns Washington's actions, but there have never been any direct protests to Congress. In its turn, it is not yet known how the protest was handed over, since the DPRK and the US do not have diplomatic relations and almost do not have official communication channels.
Nevertheless, the Central Information Agency of North Korea said that a letter of protest was sent on Friday.
Recall, as previously reported, "URA-Inform", the Federal State of Germany intends to tighten economic sanctions against North Korea. Such a statement was made by the State Secretary at the German Foreign Ministry Markus Ederer.