The FTSE 100 lost 40 points in early trade Thursday as BP shares continued to drop.
London's leading index was down 0.78%, or 39.46 points, to 5,046.40.
BP lost more than 26p, or 6.8%, to fall to 364.7p. Shares in the oil giant, traded in both New York and London, had fallen more than 4% on the FTSE Wednesday when its depositary stock, trading on the NYSE, plunged 15% to $29.20, its lowest level since 1996.
Elsewhere, Home Retail Group dropped 5.25% to 225.5p after reporting a decline in like-for-like sales in the 13 weeks to 29 May.
Its results impacted other retailers: Marks & Spencer fell 1.64% to 329.7p, while Next was down 1.63% to £20.52.
On Wall Street, late day volatility caused the index to fall, dragged lower by BP and other energy shares as the US probe of the oil spill in the Gulf of Mexico deepened.
The Dow Jones closed down 0.41%, or 40.7 points, to 9,899.3 having been more than 100 points ahead at one stage.
New York-traded shares of BP dived more than 15% to $29.90, a 14-year low. Other casualties included Exxon Mobil Corp, down 1.98% to $60.03.
In Japan, data showing a near 50% rise in Chinese exports helped the Nikkei gain 1.1%, or 103.52 points, to 9,542.65.
Putting the tech into protection
Square Mile’s series of informal interviews
Fallout from Haywood suspension
Launching later in 2019
£80bn funds under calculation