THE FTSE 100 Index lost all of the gains seen in its previous session today after a downgrade of Greek debt revived European economic worries.

The move by ratings agency Moody’s caused the Dow Jones Industrial Average to close in negative territory and dragged European markets lower, despite continued resilience in oil prices at around 75 US dollars a barrel.

The FTSE 100 Index stood 27.5 points lower at 5174.5, while exchanges in Paris and Frankfurt were down by around half a percent.

Corporate interest was focused on BSkyB after Rupert Murdoch’s News Corporation made an approach for the 61% of the satellite broadcaster it does not currently own. Independent members of the BSkyB board rejected the 700p a share proposal but left the door open to an offer of more than 800p a share.

BSkyB shares responded with a rise of 19% or 116p to 716.5p.

Meanwhile, BP shares steadied after losing as much as 10% on Monday on reports that two US senators had written to the firm demanding that it set aside 20 billion dollars (£13.5 billion) in a special account to pay for damages and clean-up costs. BP rose 1.5p to 356.95p today.

And Tesco shares were under pressure - down 1.5p to 390.15p - after the supermarket giant said UK like-for-like sales growth slowed to 0.1% in the three months to May 30.