British stocks opened lower on Friday due to caution over the escalating tensions in the Middle East, while domestic retail data showed sales stagnated in March.
The globally-focussed FTSE 100 fell 0.4% by 0714 GMT, set for its biggest weekly decline in three months.
The mid-cap FTSE 250 lost 0.6%, poised for a third consecutive week of declines. Nearly all sub-indexes traded in the red.
Travel and leisure stocks leading the declines, falling 1.2% as airlines scrambled to divert flights over Iran as tensions in the Middle East escalated.
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Meanwhile, data showed UK retail sales stagnated in March, indicating cautious consumer spending.
888 gained 2.8% after the bookmaker reported first-quarter revenue slightly ahead of its expectations, helped by strong customer volumes and expects revenue to return to growth from the second quarter.
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