President Joe Biden's decision to reject a bid by Nippon Steel to acquire U.S. Steel isn't the first time friction over trade and investment has irked Washington's closest ally in Asia.

President Biden blocked Japan's Nippon Steel from buying U.S. Steel last week, earning the approval of the United Steelworkers union, which desperately wanted the deal crushed. But steel workers themselves may be less than enthused.

US Steel and Nippon, whose $14.3 billion merger was blocked by President Joe Biden last week, filed a lawsuit against the US government Monday, claiming Biden’s executive order to bar the companies from combining was signed for “purely political reasons.