Market Talks covering the impact of U.S. Politics and White House policies on companies and markets. Published exclusively on Dow Jones Newswires throughout the day.

0538 ET - U.S. Treasury yields edge lower in European mid-morning trade while the dollar is steady as investors digest the Treasury's decision to increase long-end debt buybacks and its plan to economically isolate Iran. "Financial markets are heading into a heavy run of catalysts following their reaction to Treasury Secretary Scott Bessent's moves on long-dated Treasury buybacks and the latest sanctions against Iran," says the The Revacy Fund's Zaheer Anwari in a note. Treasury yields remain at elevated levels as markets await the next round of U.S. economic data, he says. The 10-year Treasury yield falls 1.6 basis points to 4.886%. The DXY index is stable at 99.028. (emese.bartha@wsj.com)

0447 ET - Sterling rises to a one-week high against the euro, recovering to levels seen before the U.S. Treasury announced increased buybacks of long-term securities. This signals that the positive premium in the euro has been scaled back, ING's Francesco Pesole says in a note. "If calm is indeed restored in the bond market, expect the pair to return to tracking short-term rate differentials closely." Sterling is likely to turn lower against the euro in coming months as expectations for interest-rate rises by the Bank of England look excessive, he says. The euro falls to as low as 0.8544 pounds and ING expects it to reach 0.8700 over the next few months. (renae.dyer@wsj.com)

0323 ET - Oil prices fall in early trading, with Brent crude below $90 a barrel despite U.S. plans to tighten economic pressure on Iran. The global oil benchmark is down 0.8% to $89.84 a barrel, while the U.S. gauge WTI slips 0.7% to $84.37 a barrel. Treasury Secretary Scott Bessent said the U.S. was sanctioning more than 60 entities, individuals and vessels tied to the regime, but didn't outline any specific steps against individual countries like China, a major buyer of Iranian oil. "The market seems largely unfazed by Washington's push for tighter economic pressure on Iran, with traders treating the U.S. effort to nudge partners away from Iranian trade as marginal rather than market‑moving," analysts at ING say. (giulia.petroni@wsj.com)

0255 ET - The dollar rises to a one-week high against a basket of currencies after Treasury Secretary Scott Bessent announced new sanctions aimed at Iran. Bessent warned that countries and companies that do business with Iran will face retaliation from the U.S. However, he didn't outline any specific steps the U.S. would take against individual countries, including China. The threat of exclusion from the dollar-based financial system stoked speculation that some countries and banks might buy dollars pre-emptively, lifting the dollar, IG analysts say in a note. The DXY dollar index rises to as high as 99.106. (renae.dyer@wsj.com)

2310 ET - The U.S. Treasury's potential use of its cash balance can "buy time, but it cannot buy fiscal credibility," State Street Investment Management's Masahiko Loo says, noting a CNBC report citing two senior officials that the Treasury could use its General Account to fund increased buybacks announced last week. "Buybacks may improve market functioning and temporarily stabilize the [Treasury yield] curve, but they do not reduce the debt burden itself. Nor can they fully offset fiscal concerns, rising AI-driven capital demand, or the longer-term refinancing risks associated with greater reliance on bill issuance," the senior fixed-income strategist adds. (ronnie.harui@wsj.com)

2228 ET - Copper declines in Asia trading. The market for the base metal appears to be increasingly difficult to interpret, given a new set of forces affecting prices, centered on geographic arbitrage and trade policy, say Societe Generale analysts in a note. Limited mine supply and growing demand from sectors such as artificial intelligence have generally supported prices, they note. However, tariff-related arbitrage has redirected large volumes of copper inventories toward the U.S., affecting stockpiles elsewhere and making the market difficult to analyze based on traditional frameworks alone, they add. The three-month copper futures contract on the London Metal Exchange falls 0.3% to $14,225.50 a metric ton. (megan.cheah@wsj.com)

1448 ET - President Trump's fresh threat to double auto tariffs on Canada targets an important pillar of the U.S.-Canada trade relationship, says Olu Sonola, head of U.S. economics at Fitch Ratings. Trump vows on Jan. 1, 2027 to impose a 50% duty on Canadian-made motor vehicles and on previously-exempt auto parts. Canada supplies 13% of total U.S. vehicles and parts, Sonola says. "The uncertainty alone will strain the highly integrated North American auto supply chain," the economist says. She warns that should Trump follow through with his auto threat, the duties "could force a significant and economically disruptive restructuring of Canada's auto industry, with lasting consequences for its manufacturing base and broader economy." (Paul.Vieira@wsj.com, @paulvieira)

1357 ET - Oil futures extend losses as U.S. Treasury Secretary Scott Bessent announces the plan to isolate Iran with sanctions against anyone doing business with the country. Although the sanctions are broader-reaching, much of the attention will be on the implications for Iran's oil exports, David Oxley of Capital Economics says in a note. Depending on whether the sanctions accelerate or delay a resolution to the conflict, they could still have a sizeable impact on the energy landscape, he says. "In practice, though, we suspect that the new package will have only a limited direct impact on Iranian energy flows in the short term" as most oil exports go to China which has not recognized U.S. sanctions in the past, Oxley adds. WTI is down 2.6% at $84.80 a barrel and Brent is down 2.5% at $92.99. (anthony.harrup@wsj.com)

1346 ET - Treasury Secretary Scott Bessent says the department is launching an "economic onslaught" against Iran's global financial connections. Beginning today, actions by the Treasury and other agencies will "tighten the noose" and block every potential source of revenue funding the IRGC, enforcing a "zero leakage" approach. Bessent said new sectoral sanctions target five of Iran's most vital lifelines in other countries: digital assets, technology, gold, aviation and shipping. "I want to emphasize that we are spreading out across the world as we speak...you will see a wave of sanctions when you leave this meeting today, and you should expect that cadence to continue," Bessent said. Markets showed muted initial reaction to the press conference. (jessica.coacci@wsj.com)

1140 ET--Canada's auto-parts makers are some of the hardest hit stocks on the TSX as President Trump threatens 50% tariff on the country's auto sector. Trump is planning to impose 50% tariffs on automobiles and parts from Canada starting in January 2027. The escalation comes after cross-border trade talks collapsed over the weekend after the U.S. added last-minute requests to a nearly completed deal. U.S. tariffs on Canadian automobiles now stand at 25%, with discounts for the U.S. content in cars, while steel tariffs are at 50%. Magna International, the largest auto-parts maker, is down 4%, while Linamar declined by 4.9%. Martinrea International shares are down 6.3%. (adriano.marchese@wsj.com)

1127 ET -- The Canadian dollar is weaker in trading amid an escalation in trade tensions between the U.S. and Canada. However, risks abound in attempts to short CAD, says Brent Donnelly, head of forex-research firm Spectra Markets. "I would not be chasing short CAD here," he says. "The CAD trade features too many crosswinds to make any sense, whether it's vs. GBP, JPY, USD or anything else." He adds CAD hasn't taken a substantial drubbing because forex traders are accustomed to President Trump's on-and-off trade threats. "It's hard for the market to get excited and/or scared of a theme when the theme is 18 months old and the tariff threats go on and off like Delta Wi-Fi." (paul.vieira@wsj.com, @paulvieira)

1100 ET--It would be a mistake to dismiss the impact of the Trump administration's new 50% tariff on $20 billion of Canadian goods, says National Bank of Canada economists. For sure, 80% of Canadian goods will remain exempt from U.S. tariffs. Still, for firms directly affected, National Bank says the new tariff "could simply render their products uncompetitive in the U.S. market ... A prohibitive tariff concentrated in a handful of sectors can trigger a sharp drop in exports, lost market share, factory closures and weaker investment." The economists estimate the average tariff on manufacturers will jump to 10% from the current 6% level. National Bank adds it is paramount that Canadian policymakers tackle domestic factors that thwart growth as a way to soften the tariff blow.