02:04 PM EDT, 03/11/2025 (MT Newswires) -- US benchmark equity indexes were lower intraday as President Donald Trump said he will double the proposed steel and aluminum tariffs on Canadian goods.

The Dow Jones Industrial Average was down 1.7% at 41,196.6 after midday Tuesday, while the S&P 500 fell 1.5% to 5,533.7. The Nasdaq Composite dropped 1.2% to 17,261.2. All sectors were in the red, led by industrials and health care.

Trump's latest plan to raise the metal tariffs on Canada to 50% takes effect Wednesday and comes in response to Ontario's decision to place a 25% duty on electricity sent to the US.

Last week, Trump issued temporary tariff exemptions for various goods coming into the US from Mexico and Canada. The White House recently doubled its levy on imports from China, which announced its own retaliatory duties on the US.

US Treasury yields were mixed intraday Tuesday, with the 10-year rate rising 2.1 basis points to 4.24% and the two-year rate dropping one basis point to 3.89%.

In economic news, small business optimism in the US declined more than expected in February as uncertainty on Main Street grew to the second-highest reading on record, a survey by the National Federation of Independent Business showed.

"With trade conflicts reigniting in March, the level of uncertainty has the potential to rise even higher," TD Economics said. "This would weigh on overall small business confidence, and is likely to manifest itself in weaker investment and hiring decisions."

US job openings increased to 7.74 million as of the last day of January from 7.51 million the previous month, according to the Bureau of Labor Statistics' job openings and labor turnover survey. The consensus was for a level of 7.6 million in a survey compiled by Bloomberg.

West Texas Intermediate crude oil was up 0.3% at $66.24 a barrel intraday. However, "gains were capped" amid tariff concerns, D.A. Davidson said in a note.

In company news, Verizon Communications' ( VZ ) subscriber growth is expected to be "probably soft" in the first quarter, Chief Revenue Officer Frank Boulben said. The telecommunications giant's shares were down 7.8%, the steepest decline on the Dow and among the steepest on the S&P 500.

Delta Air Lines ( DAL ) shares were down 8.3%, among the worst performers on the S&P 500. The carrier on Monday trimmed its first-quarter financial outlook.

Southwest Airlines ( LUV ) was the best performer on the S&P 500 intraday Tuesday, up 8.6%. The company lowered its first-quarter outlook for a key revenue metric and announced a policy change to begin charging certain customers for checked bags.

GE Vernova's ( GEV ) power conversion and storage business signed a memorandum of understanding with PyroGenesis to initiate discussions toward a multiyear collaboration, PyroGenesis said Tuesday. GE Vernova ( GEV ) shares were up 4.9%, among the top S&P 500 gainers.

Gold rose 0.8% to $2,922.40 per troy ounce, while silver gained 1.8% to $33.12 per ounce.