Global shares staged a rebound today after a speech by Russian president Vladimir Putin fuelled hopes of an easing in tensions over Ukraine.
Mr Putin told his country's parliament that Russia has no interest in other parts of Ukraine following Sunday's vote by Crimea in favour of joining Russia.
As the comments were viewed as a sign that an escalation of the crisis can be avoided, the FTSE 100 Index recovered from an initially lacklustre start to finish 36.9 points higher at 6605.3.
The Dow Jones Industrial Average was also higher at the time of London's close, while the US dollar strengthened against the pound as traders awaited news on the UK economy in Wednesday's Budget. Sterling was down 0.3% at 1.657 against the greenback and was also lower versus the euro at 1.191.
Cruise ship operator Carnival was among the biggest risers in London with a gain of 52p to 2433p, a rise of 2%, while Barclays added 5p to 236.05p.
Supermarket stocks held firm despite a warning from Sainsbury's that the sector is growing at its slowest pace in a decade.
The chain broke a nine-year run of sales growth by revealing that like-for-like sales excluding fuel slumped 3.1% in the 10 weeks to March 15.
But the abrupt end to Sainsbury's positive run seemed to have been priced in by markets as shares were up 2.5p to 313.9p.
Supermarkets have been under pressure since Morrisons announced last week that it had slumped to an annual loss and launched a £1 billion price war to take on the threat of the discounters Aldi and Lidl.
The latest downbeat update was shrugged off by investors, with Tesco also climbing, by half a penny to 300.25p, and Morrisons up 2.2p at 209.6p.
Elsewhere in the retail sector, shares in fashion chain ASOS slid 8% after its latest sales figures missed City expectations and it warned that margins were likely to be impacted this year by expansion costs, including in China.
The stock, which has risen from 255p at the start of 2008 to more than 7000p last month, was down by 20% at one stage - wiping more than £1 billion from its value. It later closed 526p lower at 5800p.
The ASOS warning sent smaller rival Boohoo.com down by 10% at one point but the stock market newcomer also recovered to finish 1p higher at 67.5p.
Elsewhere, shares in equipment rental firm Speedy Hire dived after it downgraded profit expectations for the year to March due to continued pressure on its international arm. Shares fell 12.5p to 64.25p, a drop of 16%
The biggest FTSE 100 risers were BAE Systems up 11.3p at 407.8p, ITV ahead 5.2p at 203p, Carnival up 52p at 2433p and Barclays ahead 5p at 236.05p.
The biggest fallers were Resolution down 22.1p at 351p, Fresnillo off 44p at 880.5p, Antofagasta down 19p at 828.5p and Next off 150p at 6565p.