By Carla Mozee, MarketWatch

LONDON (MarketWatch) -- European shares slipped Friday, as shares of banking firm BNP Paribas SA posted their sharpest decline in more than a year, but the region's equity index was holding to gains for the week as well as for the month.

The Stoxx Europe 600 was off less than 1 point at 334.38, but was on track for a 0.7% advance for the week. That would mark the seventh consecutive week of rises for the index.

The Stoxx 600 was up nearly 2% for the month, during which the pan-European gauge reached its highest level six years. Germany's DAX during May logged a record closing high, and the U.K.'s FTSE 100 hit its best level since late December 1999.

"Over here in Europe, major benchmarks are still finding much of their support built on expectations of increased stimulus next week, after European Central Bank President Mario Draghi pledged to ease monetary policy in June if necessary," said ETX Capital in a Friday note.

The euro-zone economy has been grappling with low inflation and lackluster growth. Earlier this week, Yves Mersch, an ECB executive board member, said the ECB's council members were "unanimously" comfortable with taking action at their meeting, which is set for Thursday.

Data released Friday showed Spanish inflation eased slightly in May, but the country still faced deflation risks. In Italy, the consumer-price index fell 0.1% in May from April.

The Stoxx 600 is up roughly 5% so far this year. At the same time a year ago, the index was down about 1%.

Hurting on Friday were BNP Paribas shares as they lost 4.5%. It was their worst decline since April 2013, with the move coming as the U.S. Justice Department seeks $10 billion from the French bank to resolve a criminal probe into allegations that for years it evaded sanctions against Iran and other countries.

Talks are ongoing over whether BNP will temporarily lose its ability to transfer money into and out of the U.S., The Wall Street Journal reported, citing unnamed people familiar with the matter. It's also possible that an agreement is likely weeks away and that BNP may pay less than the $10 billion the DOJ wants.

BNP shares lagged France's CAC 40 index , which fell 0.4% to 4,510.54. The index was in line for a monthly increase of 0.5%.

Miners were held lower Friday as iron-ore prices slumped. Anglo American PLC dropped 3.3%, BHP Billiton PLC (BHP) fell 2.1%, and Rio Tinto PLC (RIO) gave up 2.8%. Mining stocks put pressure on the FTSE 100, which fell 0.2% to 6,856.82. Its monthly gain stood at 1.2%.

Meanwhile, shares of Voestalpine AG lost 1.2% following a downgrade to neutral at J.P. Morgan, which cited a lack of catalysts in the short-term for the steel-product maker as reason for the move.

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