The presidential office said it welcomes U.S. President Donald Trump's decision to permit South Korea's construction of nuclear-powered submarines.

Presidential spokesperson Kim Nam-joon said in a press briefing at Gyeongju's International Media Center on Thursday that Washington had expressed strong support for Seoul's pursuit of its own nuclear-powered submarine during a bilateral summit the previous day.

The spokesperson said Trump's decision will significantly expand the South Korean military's leading role in the nation's defense and that the two sides will closely cooperate to implement the plan.

According to the spokesperson, the U.S. president stressed at Wednesday's dinner that it was bold of President Lee Jae Myung to raise the issue during the summit.

Trump did not immediately respond to Lee's request for approval, but later announced on social media that South Korea would build a nuclear-powered submarine in Philadelphia, adding that shipbuilding in the United States would soon make a big comeback.