(Sharecast News) - London's FTSE 100 was down 0.6% at 7,220.41 in afternoon trade on Thursday.
Johnson Matthey was the worst performer on the top-flight index as the speciality chemicals company said half-year pre-tax profit declined 8% while net debt rose.
Imperial Brands and Carnival retreated as their stock went ex-dividend.
On the upside, British Gas owner Centrica surged as it backed its full-year guidance and increased its efficiency savings forecast by £50m to £300m.
British American Tobacco was a high riser following reports on Wednesday that US regulators have abandoned plans to cut the level of nicotine in cigarettes.
Admiral was in the green after FTSE 250 peer Direct Line put out a well-received third-quarter trading update on Wednesday.
FTSE 100 - Risers
Centrica (CNA) 78.30p 7.70%
British American Tobacco (BATS) 2,950.00p 3.11%
Admiral Group (ADM) 2,056.00p 1.43%
Rightmove (RMV) 618.00p 1.01%
Smith & Nephew (SN.) 1,667.50p 0.94%
Coca-Cola HBC AG (CDI) (CCH) 2,421.00p 0.83%
Kingfisher (KGF) 195.25p 0.64%
Reckitt Benckiser Group (RB.) 5,930.00p 0.58%
SEGRO (SGRO) 868.20p 0.49%
Flutter Entertainment (FLTR) 8,540.00p 0.47%
FTSE 100 - Fallers
Johnson Matthey (JMAT) 3,002.00p -6.65%
Imperial Brands (IMB) 1,699.60p -3.49%
Evraz (EVR) 353.70p -2.75%
Bunzl (BNZL) 1,964.00p -2.68%
Fresnillo (FRES) 603.00p -2.65%
Carnival (CCL) 3,087.00p -2.34%
DCC (DCC) 6,362.00p -2.06%
Anglo American (AAL) 1,999.00p -2.03%
Auto Trader Group (AUTO) 528.80p -1.89%
BHP Group (BHP) 1,659.40p -1.85%