U.S. President Joe Biden plans to express concern about Nippon Steel Corp’s proposed $14.9 billion takeover of U.S. Steel Corp, a person familiar with the matter said on Wednesday, sending the U.S. company’s shares lower on bets that the deal could face greater political opposition. down nearly 13%.

The issue threatens to overshadow an April 10 summit between Biden and Japanese Prime Minister Fumio Kishida, which is aimed at strengthening the long-term security alliance between the two countries amid China’s growing power.

In December, Nippon Steel Corp (5401.T) paid a hefty premium to acquire the iconic 122-year-old U.S. steelmaker, betting that U.S. Steel (XN) would benefit from spending and spending in Biden’s infrastructure bill. Tax incentives.

However, several U.S. Democratic and Republican senators criticized the deal, citing national security concerns or questioning why the companies did not consult U.S. Steel’s main union before announcing it.

Donald Trump, Biden’s rival in November’s US presidential election, has said he would block a takeover of US Steel if elected. The White House said in December that the deal needed to be scrutinized given U.S. Steel’s central role in producing materials critical to national security.

The White House declined to comment on Wednesday, but a person familiar with the matter said Biden will make a statement about the planned acquisition before Kishida arrives for a state visit.

According to the Financial Times, which first reported the news, U.S. officials and lawyers have drafted the statement, and the White House has privately notified the Japanese government of Biden’s decision.

Japan’s embassy in Washington did not immediately respond to a request for comment.

Matthew Goodman, a trade and economics expert at the Council on Foreign Relations think tank in Washington, said the issue could overshadow the summit and cause damage to Kishida, who is already troubled politically at home.