BT shares pulled the FTSE 100 into the red after the telecoms giant revealed plans for a £530 million writedown amid a major accounting scandal at its Italian business.

London's top flight index ended flat, inching lower by 0.8 points to 7,150.34 points, dragged lower by BT shares which plunged 79.55p to 303p.

The telecoms giant warned on profits after saying it expects to take a £530m hit after accounting irregularities at its Italian division resulted in an overstatement of earnings at the division over a number of years.

The figure was revised up from a previous estimate of £145m.

In currencies, the pound was nearly flat against the US dollar at 1.253, and rose 0.09 per cent against the euro to 1.165.

Sterling stumbled earlier in the day after Britain's Supreme Court ruled that the Government is not required to consult the Scottish, Welsh or Northern Irish assemblies before kick-starting the Brexit process.

Investors were also digesting data which showed that the Government borrowed a higher-than-expected £6.9 billion in December. Economists were pencilling in a figure of £6.7bn.

Across Europe, the French Cac 40 rose nearly 0.2 per cent and the German Dax rose 0.4 per cent.

In oil markets, Brent crude prices rose 0.5 per cent to around $55.64 per barrel (£44.48) amid signs that the supply cuts by Opec and other major producers were starting to tackle the global glut.

In UK stocks, Centrica shares fell 1.7p to 225.4p. Its British Gas Business agreed to pay a £9.5m penalty after the energy watchdog said it "let customers down" following billing and complaints issues.

HSBC shares rose 2.7p to 672.8p after the high street lender said it would shut a further 62 bank branches on top of the 55 closures announced last year. It also announced that 204 IT jobs would be lost to cost cuts by year-end.

Dixons Carphone shares fell 21.1p to 315p despite notching up a six per cent surge in like-for-like sales across stores in the UK and Ireland over the 10 weeks to January 7, with analysts saying that 2017 could prove a more challenge year for the retailer.

Shares in easyJet fell 95p to 981p after revealing another £35m hit from the weak pound, and a financial impact in the "low millions" following last month's Christmas market attack in Berlin.

The biggest risers on the FTSE 100 were Anglo American up 77.5p to 1,386p, Antofagasta up 34.5p to 824p, Rio Tinto up 140.5p to 3,615p, and ITV up 8p to 209.3p.

The biggest fallers on the FTSE 100 were BT Group down 79.55p to 303p, easyJet down 95p to 981p, Dixons Carphone down 21.1p to 315p, and Paddy Power Betfair down 355p to 7,940p.