The FTSE slid into negative territory in afternoon trading following news of a record month-on-month drop in house prices.
The index is down 0.26% at 5,666.34, with mining stocks such as Kazakhmys and Antofagasta among the worst performers.
However, M&S Group has seen its price soar after positive sales news, rising 4.73% to 409.30p, while RSA Insurance Group, Man Group and GlaxoSmithKline are also performing well.
Earlier, Halifax revealed house prices fell by 3.6% in September from the previous month.
Meanwhile, on Wall Street the Dow Jones has opened steadily, slightly down 0.03% to 10,964.43 in early trading.
New figures from the Labor Department showing claims for jobless benefits fell from 456,000 to 445,000 in the week ending 2 October have boosted retail stocks in particular.
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