Technology giants Google and IBM beat estimates in the US, while closer to home consumer goods group Unilever's full-year results came in at the top end of City hopes.
The FTSE-100 Index closed up 18.5 points at 6197.6 – reaching another high since May 2008.
Unemployment data, which showed jobless claims for December dropped 12,100, lifted the pound up against the US dollar to 1.58, and up against the euro at 1.19.
Unilever was near the top of London's blue-chip risers board after its 2012 figures showed a pick-up in growth towards the end of the year, helped by continued strong demand for its products in emerging markets.
Across the year, underlying sales growth of 6.9% in 2012 lifted profits 7% to a better-than-expected £4.1 billion – pushing shares up 3%, or 75p to 2526p.
Thomson and First Choice holidays operator TUI Travel dipped nearly 5%, off 14.1p to 278p, after its German parent company said it was no longer interested in talks over an offer for the rest of the shares.
SSE was 4% lower after it announced that chief executive Ian Marchant would step down in the summer after 10 years at the helm.
Shares were off 53p to 1382p, but some 25p was due to SSE trading without the right to the latest dividend.
Outside the top flight, shares in WH Smith were lower despite a trading update which showed more success for its strategy of focusing on profitability over sales. Like-for-like revenues fell 5% in the 20 weeks to January 20, but with close management of margins and costs the company said it still delivered a good profits performance for the period. Shares were down by 2p at 650p yesterday.
Elsewhere, regional airline group Flybe's shares fell 5% after it announced around 300 jobs are to be axed as it battles to slash costs by £35 million to stem losses.
Shares in the Exeter-based carrier fell 2.5p to 47p as it also said it was putting its network of 13 UK bases under review. Further details will be released in the summer.
The biggest FTSE-100 risers were Tullow Oil, up 40p to 1195p, Unilever, Marks & Spencer, 9.4p higher at 379.1p, and Petrofac, up 35p to 1735p.
The biggest FTSE-100 fallers were TUI Travel, SSE, Standard Life, 6.8p lower at 336.3p, and Compass Group, down by 13.5p to 746p.