The White House has said that the US is "fully capable" of defending itself against a North Korean ballistic missile attack.
Asked whether North Korea's threat was being taken seriously, a White House spokeswoman said that foreign government's must be "taken at their word".
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"We are not afraid." Those were the defiant words of the Prime Minister this morning as she addressed the Commons.
Andreea Cristea, 29, remains in a critical condition after being rescued from the Thames after a terror attack along Westminster Bridge.
The Prime Minister has praised the former soldier's "huge professionalism" in trying to save the life of Pc Keith Palmer.