The split was emblematic of so many shifts in U.S. policy — including of Biden’s pledge to build trust with allies and the race against China.

By David Shepardson, Tim Kelly, Andrea Shalal WASHINGTON/TOKYO (Reuters) -U.S. President Joe Biden blocked Nippon Steel's proposed $14.9 billion purchase of U.S. Steel on Friday, citing national security concerns,

US President Joe Biden has formally blocked the takeover of US Steel by a bigger Japanese company, saying foreign ownership could pose risks for national security. The controversial decision comes a year after Nippon Steel first announced the $14.9bn (£12bn) deal, describing it as a lifeline for its smaller Pennsylvania-based rival.