Sainsbury's shares came under pressure today as the supermarket posted its first loss in a decade and warned that sales were unlikely to improve this year.

The UK's third biggest grocery chain was among the top fallers in the top-flight as it slid 3% during a session when the FTSE 100 Index stuck close to its opening mark, adding just 6.2 points to close at 6933.7.

Investors opted to remain on the sidelines on the eve of the general election and with the outcome of the monthly US jobs report also due this week.

Markets held firm despite the uncertainty after it emerged that cash-strapped Greece had managed to make a 200 million euro payment to the International Monetary Fund, as bail-out negotiations appeared to make some progress.

Meanwhile, economic data from the eurozone indicating that activity continued to grow at a steady pace in April also helped both Germany's Dax and France's Cac 40 to edge higher.

It also boosted the single currency, with the pound losing out despite separate UK data, hailed by David Cameron, showing the dominant services sector grew at its fastest pace in eight months in April - lifting hopes for a better second quarter for the overall economy.

Sterling dropped by a cent against the euro to just over 1.34 but it rose by a cent against the US dollar to a little over 1.52.

The greenback was weakened by figures from payroll processor ADP indicating that US hiring slowed in April to its weakest pace in nearly a year. It comes ahead of official jobs figures due out on Friday.

In New York, the Dow Jones Industrial Average drifted lower.

Supermarket stocks were in focus after the results from Sainsbury's and market share data from industry research group Kantar Worldpanel.

Sainsbury's dipped 8.7p to 266.3p, as it slashed its full-year dividend and reported a bottom-line loss of £72 million due to the impact of one-off property write downs, though underlying profits were better than expected at £681 million.

Tesco shares initially stumbled too but at the end of the session were just 0.1p lower at 226.8p. Morrisons added 1.9p to 189.3p.

Shore Capital retail analyst Clive Black kept his sell rating on Sainsbury's and said he was concerned about the impact that a revitalised Tesco may have on the business.

The latest till roll figures from Kantar Worldpanel for the 12 weeks ending April 26 revealed that thanks to record low grocery deflation a typical basket of everyday items is now 2.1% cheaper than a year ago.

The top-flight's biggest rise came from accounting software firm Sage after it reported a 9% increase in half-year operating profits, helped by recurring revenues growth of 8%. Shares in the North East-based company added 8%, or 39.5p to 536p.

The biggest risers in the FTSE 100 Index were Sage Group up 39.5p to 536p, St James's Place up 16p to 886.5p, Imperial Tobacco up 55p to 3175p and Vodafone up 3.6p to 232.2p.

The biggest fallers in the FTSE 100 Index were Aberdeen Asset Management down 19.5p to 431.1p, Sainsbury's down 8.7p to 266.3p, Hikma Pharmaceuticals down 44p to 1980p and Antofagasta down 16p to 782.5p.