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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Higher food and petrol prices are expected to send inflation to its highest level in 28 months when official figures are released later.
The Prime Minister will detail her 12-point plan on negotiating Britain's exit from the European Union during a speech on Tuesday.
Police investigating the disappearance of Victoria Cherry, who was last seen in October 2015, have found a body.