London's FTSE 100 Index failed to build on a new record high today, despite another batch of largely upbeat corporate results.

The FTSE 100 Index was 36.3 points lower at 7060.5, having peaked at a new intraday record of 7119.4 near the start of the session, while Pearson was the biggest faller in the top flight down 57p to 1370p amid fears over a lucrative US education contract.

A strong session for the likes of Unilever and Debenhams masked wider uncertainty over the outcome of next month's general election and whether Greece is heading towards a debt default.

The pound was one cent stronger against the US dollar at 1.49 after American homebuilders opened the spring buying season in March at a slower pace than last year. Sterling also made progress versus the weakening euro, at 1.39.

BAE Systems was one of the leading fallers in the FTSE 100 Index as its shares declined three per cent or 16.5p to 516p in the face of a ratings downgrade from UBS.

Others on the back foot included Guinness drinks giant Diageo after it said net sales declined 0.7 per cent in the quarter to March 31, with volumes also down 0.8 per cent. That disappointed investors as shares fell more than three per cent or 70.5p to 1896.5p.

In contrast, Unilever shares were the strongest riser in the top flight surging almost three per cent after the consumer products giant, which makes Flora spread and Pot Noodle, said underlying sales grew by a better-than-expected 2.8 per cent in the first quarter of the year.

The stock was up 77p at 3011p as chief executive Paul Polman said the company was now starting to see more tailwinds than headwinds in its core markets.

Investors were also encouraged that Unilever had not been impacted by recent evidence of slowing economic growth in China.

Outside the top flight, shares in Debenhams rose almost seven per cent or 5.3p to 84.9p after it reported a better-than-expected four per cent rise in half-year profits to £88.9 million.

The improvement follows changes in the chain's promotional and online offer, as well as its renting out of some of its under-used space to other retailers.

In other retail updates, WH Smith shares were 17p lower at 1385p after a continuation of its strategy of focusing on margins rather than sales growth resulted in a four per cent rise in half-year profits to £72 million. This was after a two per cent fall in like-for-like sales.

Mothercare shares jumped six per cent or 12.8p to 224.8p after like-for-like sales jumped 5.1 per cent in the final 11 weeks of the financial year to March 28.

The improvement follows a £100 million fundraising last October which has helped fund the modernisation and digital overhaul of the UK business.

The biggest risers in the FTSE 100 Index were Unilever up 77p at 3011p, Aggreko up 31p at 1621p, Randgold Resources up 95p at 5080p and GKN up 6.5p at 370.6p.

The biggest fallers in the FTSE 100 Index were Pearson down 57p at 1370p, Diageo down 70.5p at 1896.5p, Meggitt down 17.5p at 546.5p and BAE Systems down 16.5p at 516p.