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Shares in oil companies weighed on the UK stock market as crude prices remained under pressure.

At the close, the FTSE 100 index was down 8.5 points, or 0.11%, at 7,439.29.

Shares in Royal Dutch Shell and rival BP closed slightly up after struggling earlier in the day as oil traded above $45 a barrel.

On Wednesday, the price of Brent crude oil had fallen to $44.35 a barrel, its lowest since November, although it recovered to $45.61 on Thursday.

Oil prices have been dragged lower by excess supplies on the global market, despite the efforts of the Opec producers' cartel to limit output in order to push prices higher.

Pharmaceuticals firm Shire was the top riser in the FTSE 100, up 3.7%, after the European Medicines Agency validated its marketing authorisation application for Veyvondi, which treats an inherited bleeding disorder called von Willebrand disease.

Outside the FTSE 100, shares in Imagination Technologies jumped 16% after the company put itself up for sale.

Imagination is in dispute with its largest customer, Apple, after the US tech giant announced earlier this year that it planned to stop using Imagination's technology in its products.

On the currency markets, the pound slipped 0.1% against the dollar to $1.2658 and was up 0.08% against the euro at 1.1355 euros.