South Korea to build nuclear sub at home, seeks US enriched fuel

Asked about South Korean officials' comments suggesting that the submarine might be built there rather than in the United States, a White House spokeswoman on Thursday referred back to Trump’s comment that it would be built, "in the Philadelphia Shipyards, right here in the good ol’ USA."

Meanwhile, South Korea and the US are working on a joint fact sheet that contains details of their recently agreed deal on a $350 billion investment package in exchange for lower tariffs and on security issues such as modernising the alliance.

The fact sheet is taking longer to finalise because relevant US ministries are still giving feedback and there continue to be adjustments on the wording, the official said.