Nucor Corporation's stock surged 9.43% in pre-market trading on Monday, following President Trump's announcement of plans to impose steep 25% tariffs on imports of steel and aluminum. The proposed tariffs are aimed at protecting domestic steel producers like Nucor from foreign competition.

As a leading U.S. steel manufacturer, Nucor is expected to benefit significantly from the import restrictions. The tariffs could boost demand for Nucor's products and allow the company to raise prices, supporting higher profitability.

Investors reacted positively to the tariff news, driving up shares of Nucor and other major domestic steel companies. The Trump administration's move is seen as part of a broader protectionist trade agenda to support American industries and reduce the nation's trade deficits.