Shares in chipmaker Nvidia closed Monday's session nearly 2% in the red, after outgoing US president Joe Biden's administration released an updated export rule aimed at controlling the flow of AI chips to China.
"Artificial intelligence is quickly becoming central to both security and economic strength," the White House said in a statement on Monday. "The United States must act decisively to lead this transition by ensuring that US technology undergirds global AI use and that adversaries cannot easily abuse advanced AI."
Some 18 "key" allies, including the UK, will be exempt from the restrictions.
In response, Nvidia vice president of government affairs Ned Finkle said in a statement that the "misguided 'AI diffusion' rule ... threatens to derail innovation and economic growth worldwide".
Other AI-related and broader technology stocks also fell, including data analytics software provider Palantir (PLTR), which fell more than 3% on Monday.
Shares in Trump Media surged nearly 22% on Monday, a week before US president-elect Donald Trump is due to be inaugurated for a second nonconsecutive term.
Electric carmaker Tesla (TSLA) was another stock that rose on Monday ahead of Trump's return to the White House, closing the session 2% in the green. Tesla CEO Elon Musk is a close ally of Trump and has been appointed to co-lead the extra-governmental Department of Government Efficiency (DOGE).
Moderna stock slid nearly 17% on Monday, after the US biotech firm slashed its 2025 sales forecast range by $1bn.
Moderna said in a business update on Monday that it expected revenue for 2025 to come in at the range of $1.5bn to $2.5bn, which was down from a previous forecast of $2.5bn to $3.5bn.
The company said it had seen "minimal sales" of its mRESVIA vaccine, for respiratory syncytial virus, which had received regulatory approval in 2024.
For 2024, Moderna said it had generated $3bn to $3.1bn in product sales and an ending cash balance of around $9.5bn.
The biotech firm said it expected to cut cash cost expenses by $1bn in 2025 and planned for an additional $500m in reductions in 2026.
Stéphane Bancel, CEO of Moderna, said: "We remain focused on our three strategic priorities: driving sales growth, delivering up to 10 product approvals over the next three years, and reducing costs across our business."
Investors cheered Ocado Retail's fourth quarter trading results, with shares in the online grocer surging nearly 11% on Tuesday morning, after the company said it had delivered another "record-breaking Christmas".
Ocado said that its joint venture with M&S (MKS.L) had generated year-on-year revenue growth of 17.5% in the fourth quarter, rising to £715.8m ($872.2m).
The grocer said volumes on Ocado.com had grown by 17% compared with the same period last year, while average orders per week were also up nearly 17% to 476,000.
Chris Beckett, head of equity research at Quilter Cheviot, said: "For the company to achieve meaningful uplift in its share price, it needs to secure more international orders for its warehouse and logistics technology.
"These partnerships, which form the backbone of its global expansion strategy, are essential for diversifying revenue streams and demonstrating scalability. Success on this front could act as a catalyst for re-rating its valuation in the market."
Retailer JD Sports warned on profits once again on Tuesday, which prompted shares to drop nearly 10%.
The sportswear retailer said it now expected profit before tax and adjusting items to come in at between £915m and £935m for the year. That's down from its previous guidance of profits coming in at the lower end of £955m to £1.04bn.
JD Sports posted revenue growth 3.4% for nine weeks to 4 January and 1.5% growth in life-for-like revenue over December.
Régis Schultz, CEO of JD Sports Fashion Plc, said: "While I am pleased overall with our performance, market headwinds were higher than we anticipated and therefore our full year profit forecast is slightly below our previous guidance.
"With these trading conditions expected to continue, we are taking a cautious view of the new financial year."
Russ Mould, investment director at AJ Bell (AJB.L), said that "Schultz joined as the cool cat boss in 2022 and a year later unveiled his plans for JD to be a 'leading global sports-fashion powerhouse'."
"His nine lives are nearly up as the business has spluttered under his leadership and the goal of achieving £1bn profit has been kicked further down the road," Mould added. "The share price has fallen by a third since he become CEO and investors will be losing patience fast."
Other companies in the news on Tuesday 14 January:
