The FTSE 100 posted a modest gain midweek, driven primarily by strength in the energy sector amid rising oil and gas prices linked to heightened geopolitical tensions. Brent crude oil increased by 1.3 percent, reaching $115.32 per barrel, while Europe’s leading natural gas contract briefly touched €100 per megawatt hour. These price levels approach the highs last seen in 2022 following Russia’s invasion of Ukraine and reflect renewed concerns over supply amid escalating conflict in the Middle East, including fighting in Yemen and an attack on Saudi Arabian infrastructure.

Market analysts predict that gas prices could remain elevated for at least another year, even if the ongoing conflicts are resolved and winter temperatures are mild. This outlook is underpinned by Europe's need to replenish gas storage reserves, which have been drawn down to record lows over recent months.

Among the top performers on the FTSE 100, SSE, a major electricity generator, saw its shares rise by 114 pence, or 4.6 percent, to £26.04, marking it as the second-largest gainer on the index. Centrica, the owner of British Gas, followed closely with a 3.8 percent increase to 156.25 pence. Oil giants BP and Shell also benefitted, with BP shares up 1.2 percent to 619.75 pence and Shell climbing 0.7 percent to £39.56. Metals and energy firm Metlen Energy & Metals added 2 percent, closing at 49.5 pence.

The FTSE 100 ultimately advanced 7.96 points, or 0.1 percent, to finish at 10,694.5. On the downside, housebuilders were the main drag on the index. Barratt Redrow’s shares dropped 6.6 percent to 315.75 pence, contributing to a wider selloff among homebuilders that erased over £1 billion in combined market value. This decline followed analyst warnings that the government’s new Your First Home scheme is unlikely to significantly increase housing supply.

Retailer J Sainsbury also weighed on the market, falling 2.5 percent to 338.5 pence, continuing to feel the effects of a downgrade by Deutsche Bank analysts from “buy” to “hold” issued the previous day.

Meanwhile, the more domestically focused FTSE 250 index declined by 77.11 points, or 0.3 percent, to 24,639.26. Housing-related shares were among the worst performers, with Taylor Wimpey down 7.3 percent to 78.75 pence, Persimmon off 6.9 percent at £12.305, and Vistry Group declining 5.9 percent to 260 pence. Property website Rightmove fell 4.7 percent to 508.5 pence, reflecting broader concerns about the UK housing market amid policy uncertainties.