By Sara Sjolin, MarketWatch

LONDON (MarketWatch) -- European stock markets rose for the first time in three days on Wednesday after euro-zone consumer confidence data rose to the highest level in more than six years in May.

The Stoxx Europe 600 index rose 0.6% to close at 340.34, ending at the highest level in a week.

Posting the biggest gain in the benchmark, shares of Britvic PLC rallied 7.9% after the soft-drinks maker lifted its half-year dividend by 13%.

A.P. Moeller-Maersk A/S gained 3.8% after the Danish oil and shipping giant upgraded its full-year outlook after posting a 62% increase in first-quarter profit.

On a more downbeat note, shares of Wm Morrison Supermarkets PLC dropped 2.2% after Deutsche Bank cut the food retailer to sell from hold. The analysts argued that after a 10% rally over the past two weeks, there aren't enough strong fundamentals to push the stock higher.

Shares of BNP Paribas SA gave up 1.3% after HSBC cut the French bank to neutral from overweight and after Bloomberg reported U.S. authorities are seeking $5 billion from the company to settle a probe into sanctions violations.

Euro-zone consumer confidence

More broadly, investors were encouraged by strong consumer-confidence data for the euro zone for May. Confidence rose to -7.1 from -8.6 in April, marking the highest level since October 2007 and beating analyst expectations.

The data come ahead of the euro-zone purchasing managers' indexes released on Thursday morning. Any weakness in the data could increase bets that the European Central Bank will loosen monetary policy at its June meeting, as ECB policy makers have hinted heavily that they're ready for some easing action.

The FTSE 100 index rose to close 0.3% higher at 6,821.04, while France's CAC 40 index picked up 0.4% to 4,469.03. Germany's DAX 30 index added 0.6% to 9,697.87.

European Parliament elections

The European Parliament elections were also in the spotlight, with the voting kicking off in the U.K. on Thursday. The last countries vote on Sunday, and the results from all 28 member states should start to be revealed on Sunday night.

After a period of low growth and tough austerity measures, euroskeptic parties are expected to get more seats in parliament than ever, which could turn out to be a decisive factor in Europe's future. However, several economists note that the anti-European parties are opposing the EU for different reasons, which could make it hard for them to join forces and actually pose a threat to further European integration.

"The risk of anti-European parties winning strong support is counterbalanced by their heterogeneity and lack of majority," analysts at Société Générale said in a note ahead of the elections.

BOE minutes

In the U.K. on Wednesday, minutes from the Bank of England's May policy meeting showed all nine members of the Monetary Policy Committee voted in favor of keeping rates at a record low of 0.5% and making no changes to the bank's quantitative-easing program. Analysts noted that the minutes showed a more hawkish tone, as there was a "range of views" on the Monetary Policy Committee and that "for some members the monetary policy decision was becoming more balanced."

Nick Beecroft, senior market analyst at Saxo Capital Markets, said in emailed comments that we should expect to see the first dissenting votes emerge over the next quarter.

"But maybe as early as next month if this morning's release showing a surge in retail sales in April is indicative of an acceleration in growth," he added.

The pound (GBPUSD) rose after the minutes, trading at $1.6870, up from $1.6842 late Tuesday.

Minutes from the U.S. Federal Reserve's latest meeting were due after the European market close.

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