By Sara Sjolin, MarketWatch

LONDON (MarketWatch) -- U.K. stocks reversed course and finished higher Monday, with shares of Randgold Resources Ltd. and other miners gaining as tensions between Russia and Ukraine appeared to escalate.

The FTSE 100 rose by 0.3% to end at 6,583.76, winning back a small portion of last week's loss of 2%.

U.K. stocks sustained gains after U.S. stocks opened higher following better-than-expected quarterly results from Citigroup Inc. (C) and U.S. March retail sales, and after sharp losses recently for Wall Street's benchmarks.

But stocks in London had been down by nearly 1% during Monday's session as investors monitored events in Ukraine, where pro-Russia militants continued to occupy official buildings after a government deadline to disarm passed. Earlier, Kiev said a serviceman was killed and five wounded after camouflaged gunmen fired on government troops near Slovyansk, about 240 kilometers from Ukraine's border with Russia, according to Bloomberg. Ukraine, Russia, the U.S. and European Union are scheduled to hold talks in Geneva on April 17 to resolve the crisis, which unfolded in late February when Russian troops seized the Ukrainian peninsula of Crimea.

The nervousness over Ukraine lured investors into safe-haven gold (GCM4), which rose more than $8 an ounce and gave a lift to precious-metals miners. Randgold picked up 3.6%, Fresnillo PLC rose 2.6% and Antofagasta PLC gained 2.1%.

Energy firms turned higher, with Royal Dutch Shell PLC (RDSB) rising 1%, BG Group PLC ending up 0.6%, while Tullow Oil PLC topped the sector with a 3.9% jump. Shares of BP PLC (BP), however, finished down by 0.2%.

Among other resource firms, shares of Glencore Xstrata PLC (GLCNF) gained 2%. The mining major said on Sunday it agreed to sell its Las Bambas Peruvian copper project to a Chinese consortium in an all-cash deal worth at least $5.8 billion.

There was no relief for housing stocks Monday after a report showed U.K. housing prices climbed 2.6% in April to a new record high for a second consecutive month. Stock in Barratt Developments PLC fell 3.8% and Persimmon PLC pulled back 2.7%.

Online real estate agency Rightmove said the average asking price for homes advertised for sale on its website rose by GBP6,632 pounds ($11,131) in April to GBP262,594.

Also ended lower, GlaxoSmithKline PLC lost 0.6% after a BBC "Panorama" report that the British drug maker is facing a criminal investigation in Poland for allegedly bribing doctors to promote the company's Seretide asthma medication. In a statement, GSK said it disciplined an employee in 2011 over "inappropriate communication" in its Polish program and that it continues to investigate as it cooperates with Poland's anti-corruption bureau.

But Tesco PLC shares were a bright spot, rising 3% ahead of the supermarket chain's quarterly results due Wednesday. Shares of rival J Sainsbury PLC leapt 5.5%.

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