Escalating tensions in the Ukraine put a dampener on an otherwise positive session for markets after US tech giants Apple and Facebook beat expectations.
The FTSE 100 had been more than 40 points higher as traders reacted to good news from Wall Street the night before, but fell back as it emerged that the Ukrainian military was moving into quash pro-Russian separatists.
Jasper Lawler, analyst at CMC Markets, said: “The situation has been bubbling away in the background for months now and has the potential at any time to flare up and send cautious investors to safe-heavens.”
But in a sign that appetite for shares remains strong, the Footsie recovered some gains towards the close, ending 28.26 points higher at 6,703.
Among the biggest risers, mining giant Anglo American lifted 19.5p to 1,566.5p after its first-quarter update showed an 18 per cent year-on-year rise in copper production.
The better-than-expected performance gave a boost to other stocks in the sector, with rival Rio Tinto cheering 29.5p to 3,278.5p.
AstraZeneca continued to benefit from reports last weekend linking it to a possible takeover approach from US firm Pfizer. The company remained silent on the bid interest but the stock still rose a further 3 per cent or 132.5p to 4,175p as it confirmed it will advance four drugs in oncology and respiratory disease for late-stage testing.
Its shares have now surged by around 12 per cent this week. Fellow pharmaceuticals company Shire climbed 59p to 3,248p.
Consumer goods firm Unilever was one of the biggest fallers in the top flight after it reported slower growth in emerging markets, albeit with a rise of 6.6 per cent in revenues. Shares were 2 per cent or 44p lower at 2,590p.