STORY: Joe Biden is close to blocking Nippon Steel’s takeover of U.S. Steel.

That’s according to two Reuters sources.

The news comes amid growing bipartisan opposition to the $14.9 billion deal.

But U.S. Steel has warned that any failure to proceed could put thousands of jobs at risk, and force it to close some facilities.

Even so, the Reuters sources say a block could be announced as early as this week.

Shares in the U.S. firm plunged 17.5% Wednesday after the likely veto was first reported by the Washington Post.

Nippon Steel shares initially fell in early trade Thursday, but later rallied.

Biden is expected to cite national security risks for blocking the takeover by the Japanese firm.

And that’s unlikely to go down well in Tokyo - one of Washington’s closest allies.

However, U.S. Steel has become a hot button issue in America’s closely fought presidential election.

It’s based in Pennsylvania - a crucial battleground state that some think could determine the result of the vote.

Addressing a rally there earlier in the week, Democrat candidate Kamala Harris said she opposed the deal:

“U.S. Steel is an historic American company, and it is vital for our nation to maintain strong American steel companies. And I couldn't agree more with President Biden, U.S. steel should remain American owned and American operated. And I will always have the back of America's steel workers.”

Republican candidate Donald Trump has also pledged to block the deal if elected.

A White House spokesman declined to comment on Biden’s intentions.

U.S. Steel said it would pursue all legal avenues to ensure the takeover got done.

Nippon Steel called on Washington to handle the matter in accordance with the law.