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FTSE 100 down 0.5%, FTSE 250 falls 0.4%

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Rio Tinto's iron ore business hit by lower prices

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Centrica ( CPYYF ) warns of profit miss, pauses share buyback

By Tharuniyaa Lakshmi

Feb ​19 (Reuters) - London's FTSE 100 dipped from record

highs ‌on Thursday as Rio Tinto's shares fell after the global

miner's annual earnings missed ⁠expectations, while simmering

U.S.-Iran tensions kept investors cautious.

The blue-chip index ⁠fell 0.5% after closing at a

record high for ‌two straight sessions. ‌The domestically focused

mid-cap FTSE 250 was down 0.4%.

Rio Tinto fell 3.6% after ​the miner reported flat annual

earnings as ‌lower prices at its mainstay iron ore business were

offset by a strong performance in its copper ​division.

Other London-listed miners also fell ​after copper ‌prices

were hit by a firmer dollar, rising inventories and reduced

demand because of the Lunar New Year holiday in ⁠China, the

world's biggest metals consumer.

"A stronger US dollar - at one-month ⁠highs amid

flight-to-safety flows - added pressure on precious and base

metals, weighing on UK mining stocks, putting a dent in the FTSE

100's stellar performance," said Axel Rudolph, senior financial

analyst at IG.

Investors ⁠around ‌the globe have been unnerved by U.S.-Iran

tensions over ‌Tehran's nuclear program, with oil prices rising

by more than 2%.

UK ⁠stocks have been finding broad support from upbeat

corporate earnings, expectations of monetary policy easing as

well as inflows from investors looking to diversify away from

U.S. stocks that have been pressured by AI-disruption concerns.

On Thursday, British Gas owner Centrica ( CPYYF ) was down 5.1%,

the biggest faller on the ​blue-chip index, after warning that

2026 profit at its energy trading arm would miss forecasts and

pausing its share buyback programme after reporting ​a 39% drop

in annual ‌profit.