By Sitaraman Shankar

LONDON (Reuters) - European shares ended lower on Monday, breaking a three-day winning streak, as weaker techs and telecoms offset the impact of surprisingly robust U.S. service sector figures.

The pan-European FTSEurofirst 300 index of top European stocks ended down 0.25 percent at 1,357.99 points. With UK markets closed for a public holiday, volumes were thin.

Tech stocks weighed after Microsoft walked away from a bid for Yahoo. Chip equipment maker ASML lost 2.3 percent, and in the telecom sector, Alcatel-Lucent, Ericsson and Nokia fell 1.1-1.9 percent.

Stocks got a brief fillip from data that showed the U.S. service sector grew in April for the first time in four months, adding to signs that the United States might skirt a recession.

But oil hitting a record above $120 a barrel weighed on the broader market.

Investor focus moves to a heavy earnings day on Tuesday, when Swiss bank UBS, among the lenders worst hit by a global credit crisis, is expected to report a big first-quarter loss.

"The earnings season has been mixed with some pronounced positives and some negatives. All in all one might say the earnings development has not been as bad as one feared, given the macro backdrop," said Tammo Greetfeld, strategist at UniCredit in Munich, Germany.

"But the combination of the outlook statements and the expected macro data should not be good enough to give equity markets a lasting positive stimulus from current levels," he added.