UBS boosts European shares but Greek shares fall on debt concerns
* FTSEurofirst 300 up 0.6 pct, lifted by surge in UBS
* Athens' ATG index down 3 pct as debt worries weigh
* Asset performance in 2015: link.reuters.com/gap87v
By Sudip Kar-Gupta
LONDON, May 5 (Reuters) - European shares gained on Tuesday on the back of a rise in Swiss bank UBS, although the Greek stock market fell due to renewed concerns over the country's debt situation.
Greece's benchmark ATG equity index fell 3 percent, underperforming a 0.6 percent rise in the pan-European FTSEurofirst 300 index.
Traders cited concerns that the International Monetary Fund (IMF) may cut a funding lifeline to Greece unless its European partners accept more debt writedowns as weighing on the Greek market, with Greek bond yields also rising.
Greek Prime Minister Alexis Tsipras and German Chancellor Angela Merkel held a phone conversation on Monday night to discuss talks with international creditors.
Differences over pension and labour reforms have dogged negotiations between Tsipras's leftist government and its EU/IMF lenders. Athens, kept afloat by a 240 billion euro ($266 billion) bailout, needs fresh funds as it is running out of cash. Continuación...