Wednesday close

London's benchmark FTSE 100 Index flirted with the 4200 barrier before slipping back below its opening mark.

The blue-chip index spent much of the session in positive territory but eased following a weak start to trading in New York, eventually closing 4.9 points lower at 4180.7.

Pharmaceuticals giant AstraZeneca was 2% higher, or 47p, at 2536p, after it announced it had received regulatory approval in the US for its cholesterol-lowering drug Crestor.

Rival GlaxoSmithKline also benefited with a 9p gain to 1220p.

But the lacklustre performance of the FTSE 100 also reflected the fact that a number of blue-chip stocks went ex-dividend - meaning the price of individual shares lost the value of their previously announced shareholder payout.