The FTSE 100 came within touching distance of 10,500, despite heavy losses on Wall Street and concerns about stocks vulnerable to artificial intelligence.
Having only reached the 10,000 mark for the first time in early January, the blue-chip index rose as high as 10,481 yesterday, a new intra-day peak.
The index ended the day up 0.9 per cent, or 87.75 points, at a record close of 10,402.34, taking gains for 2026 so far to nearly 5 per cent.
Meanwhile, the FTSE 250 gained 0.2 per cent, or 42.78 points, to close at 23,333.15 as it edged back towards its all-time closing high of 24,250 in 2021.
The rally came despite a tech-stock rout in New York where the Nasdaq fell 1.3 per cent and S&P 500 dropped 0.3 per cent, although the Dow Jones Industrial Average was up by 0.5 per cent.
London-listed Shell rose 2.8 per cent while BP gained 2.4 per cent as mounting tensions between the US and Iran drove the oil price higher, with Brent crude heading back towards $70 a barrel.
Rally: Having only reached the 10,000 mark for the first time in early January, the FTSE 100 blue-chip index rose as high as 10,481 yesterday, a new intra-day peak
Susannah Streeter, chief investment strategist at Wealth Club, said: ‘London’s FTSE 100 has scaled fresh heights as its defensive qualities shine once again in an uncertain world.
‘Investors are grappling with the fallout from a tech sell-off and are assessing deteriorating relations between the US and Iran.’
Oil has seesawed this week between news of talks to de-escalate tensions between the US and Iran, and heightened fears of potential disruption to oil flows through the Strait of Hormuz.
‘Oil would be lower without Middle Eastern sabre-rattling,’ said analysts at oil trading broker PVM.
Bitcoin, which peaked above $120,000 in October, fell towards $70,000 yesterday, taking losses since the peak to 40 per cent.
Gold and silver continued their wild swings, with bullion passing $5,000 an ounce again before giving up its gains.
Back on the stock market in London, software stocks Relx and Sage extended their losses after Tuesday’s dramatic sell-off following the launch of Anthropic’s AI tool for the legal sector.
But the FTSE 100 benefited from gains elsewhere, as GSK shares hit their highest for more than a quarter of a century after a positive update, and Beazley climbed after backing an £8billion takeover by Swiss insurance giant Zurich.
Also rising was betting giant Entain after it announced that BetMGM, its joint venture with MGM Resorts, beat expectations last year.
Hailing a ‘cracking day’ for London, Saxo investor strategist Neil Wilson said: ‘Risk sentiment seems to be blowing our way.’
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