The FTSE 100 clawed back some ground after a positive start to trading on Wall Street this afternoon.
Approaching close the UK's leading index was broaldy flat on the day at 6,561, having been 46 points down in the morning (see below).
US shares got a boost from better-than-expected quarterly results from banking giant Citigroup and the biggest rise in 18 months in retail sales. The S&P 500 rallied 0.8% to 1,830.
BP weighs on FTSE as Russia tensions rise
10.46: The FTSE has slid as mounting tensions between Russia and the Ukraine took their toll on sentiment.
The FTSE 100 shed 46 points, or 0.7%, as a deadline set by the Ukrainian government for armed pro-Russian forces to leave occupied buildings in the east of the country passed.
There has been no immediate action from either side in the stand-off, but as the United Nations security council held an emergency session to discuss the crisis at Russia's request, markets have taken fright at the escalating tensions.
'One thing certainly adding to the risk-off sentiment will be the developments in the Ukraine,' said Jonathan Sudaria, dealer at Capital Spreads. 'There had been hopes that the situation may have climaxed in the annexation of the Crimea, but with pockets of pro-Russian support springing up in cities across the east of Ukraine, and authorities in Kiev looking like they're about to lose their patience with diplomacy, it's clear that this is only the opening chapter in what could be a formative moment for geopolitical relations.'
The gold price inched higher on the market unease, reaching $1,324.65, up 0.5%.
BP (BP.L), which has a stake in Russia's biggest oil producer Rosneft, fell 6.6p, or 1.4% to 468.8p.
Lloyds Banking Group (LLOY.L) shed 2.8p, or 3.8%, to 70.2p, after reports in The Sunday Telegraph that it would launch an initial public offering of TSB in the middle of May at a valuation lower than had been expected.
Glencore Xstrata (GLEN.L) added 2p, or 0.6%, to 313.5p as it agreed the sale of its Las Bambas copper mine project. Investec analyst Marc Elliott retained a 'reduce' recommendation but upped his target price to 303p on the sale. 'In our view the key positive is reducing the balance sheet risk against the threat of weaker earnings from depressed commodity prices, particularly coal and copper, in the short to medium term,' he said.