The pan-European STOXX 600 index was flat at the close after oscillating between positive and negative territory throughout the day.

On the month, the STOXX 600 rose 3.2 percent, extending gains through a fourth straight month -- its longest winning streak since May 2017.

Rising oil prices and positive euro zone economic growth and employment data helped calm investor sentiment bruised by some poor earnings from regional companies, and weak factory data from China that cast a shadow over global growth.

"The stuff that matters the most for long term demand -- the services, labour market -- that in the euro zone is in good shape," said Kallum Pickering, senior economist at Berenberg.

On the day, London's FTSE 100 underperformed, down 0.3 percent as miner Glencore weighed, while most other major country indices ended higher.

Banks were the biggest weight on the pan-regional index, with Danske Bank, caught up in a massive money laundering scandal, falling nearly 10 percent as it lowered its 2019 outlook after a disappointing first quarter.

Banco Santander, the euro zone's biggest bank by market value, slipped after first-quarter net profit dropped.

Standard Chartered, however, advanced after it announced plans for up to $1 billion of share buybacks, the bank's first in at least 20 years.

Data from China, a big consumer of metals, weighed on basic resources stocks, which were the biggest percentage losers. Glencore's move to cut its copper output forecast also weighed on the sector.

On the other hand, oil majors were the biggest boost to the region as crude prices rose.

Apple supplier AMS soared 21.2 percent, and posted its biggest one-day jump since October 2017 after it beat forecasts for first-quarter profit and gave an upbeat outlook for the second quarter.

"It's the good news of a strong outlook for second quarter sales versus expectations," said Martin Moeller, a Swiss and Global Equity portfolio manager at UBP.

"This comes after the bad news from Infineon and AMS in February ... Also, investors have been nervous about oversupply and high inventories in semiconductors, especially after the recent Intel forecast cut," he said.

AMS reported results before Apple's quarterly report due late on Tuesday.

Also helping the chip sentiment was an upbeat forecast from Samsung Electronics Co Ltd for the second half of the year.

(Reporting by Agamoni Ghosh and Medha Singh, Editing by Catherine Evans)

By Susan Mathew