London's FTSE 100 index edged down 0.1% to around 10,486 in early trading Monday, despite a majority of its members moving higher. The benchmark's weighted structure meant that declines from heavyweight stocks AstraZeneca and HSBC overshadowed advances from energy majors BP and Shell.
BP shares climbed 2.2%, while Shell added 1.1%, buoyed by a 4.3% surge in Brent crude to $79.31 a barrel. The oil price spike followed escalating tensions in the Gulf region, with Iran reportedly shutting the Strait of Hormuz. U.S. officials noted that around 20 ships had transited the passage in the past day, though tracking data showed limited movement.
Conversely, AstraZeneca fell 1.4% and HSBC slipped 0.6%, dragging the index lower. The divergence highlights the FTSE's concentration risk, where a handful of large-cap stocks can disproportionately move the market. Based on estimated weights from Vanguard's FTSE 100 tracker, AstraZeneca and HSBC together shaved about 0.17 percentage points off the index, while BP and Shell contributed roughly 0.15 points. Without the energy gains, the FTSE would have been about 0.26% lower; without the pharma and banking declines, it would have been 0.06% higher.
The broader market also felt the pinch from rising UK borrowing costs. The yield on Britain's 10-year government bond rose three basis points to 4.91%, pressuring domestic-focused stocks. The FTSE 250, which has greater exposure to the UK economy, dropped 0.18% to 23,329.43, suggesting the oil-driven boost was largely confined to major energy names.
In a bright spot, housebuilders rallied on speculation that Labour's Andy Burnham might revive the Help to Buy scheme. Persimmon gained about 3%, and Barratt Redrow rose 2.6%. The previous Help to Buy program, which required a 5% deposit and offered a government equity loan, stopped accepting new applications in 2022. However, the rally hinges on unapproved policy, and with gilt yields near 5%, mortgage affordability remains a challenge.
AstraZeneca's decline accelerated after HSBC analysts downgraded the stock to 'hold' from 'buy' and slashed their price target to £137.50 from £165. The downgrade followed news that Wainua missed its primary endpoint in a late-stage heart disease trial. AstraZeneca shares have now fallen 11.2% over the past week, adding pressure on the FTSE.
The pound weakened 0.2% to $1.3383, while investors eye upcoming U.S. CPI data for June and Fed Chair Kevin Warsh's congressional testimony. Both events could influence bond yields and the dollar. In London, a drop in inflation or oil prices might broaden the market rally beyond energy stocks. But another oil spike would further highlight the FTSE's sector concentration.
Analysts remain cautious. Jefferies' Mohit Kumar expressed hope for renewed trade talks, while independent analyst Nick Bubb was skeptical about the rumored October UK budget, saying 'Good luck with that timing.' The housebuilder rally, meanwhile, relies on policy that hasn't been approved, and prolonged disruption at Hormuz could push fuel prices higher, stoking inflation and hitting domestic stocks.
