Europe markets close lower; UK election, ECB in focus; Banco Popular tumbles 6%

European markets closed lower on Tuesday as investors erred on the side of caution ahead of the U.K. general election and European Central Bank meeting later in the week.

The pan-European Stoxx 600 ended down 0.67 percent with most sectors and major bourses in negative territory. Health care was among the worst performing sectors following news that a clinical trial from Roche resulted in only a modest benefit for women with a specific type of disease. Roche shares slipped over 5.5 percent.

Banco Popular was once again among the worst performing stock as its shares tumbled more than 6 percent on Tuesday. Barclays said it had cut its price target on the Spanish lender, which has struggled to convince investors since reports emerged last week that it will have to be wound down if it doesn't find a buyer.

More broadly, banking stocks ended down by around 0.6 percent as investors do not expect the ECB to change its monetary policy stance on Thursday. Italian banks were lower, with BPM down over 1.5 percent. According to Reuters, the central bank of San Marino, a microstate in Italy, plans to inject money into its ailing lenders which have 1.8 billion euros ($2 billion) in gross bad loans.

Meanwhile, in the U.S., the Dow Jones industrial average and broader S&P 500 both continued under pressure as geopolitical uncertainties weighed on sentiment.

Elsewhere, British luxury retailer Burberry fell over 3 percent after HSBC downgraded it from "hold" to "reduce".

EasyJet closed slightly lower despite reporting an increase of 9.5 percent in the number of passengers in May.

Arcelormittal slumped more than 2 percent on Tuesday. The Italian government has decided to support the firm's 1.8 billion euro ($2 billion) offer to acquire Ilva Steel alongside Marcegaglia.

Vestas Wind Systems closed at the top of the European benchmark on Tuesday following a target price upgrade by Goldman Sachs. It jumped more than 4.7 percent.

Oil prices were little changed on Tuesday as a political rift in the Middle East appeared to cap any significant gains. Countries such as Saudi Arabia, Egypt and the United Arab Emirates decided to cut ties with Qatar blaming it of supporting Islamist militants.

In terms of data, retail sales in the euro zone rose slightly in April, the fourth consecutive monthly rise, thanks to increased purchases of food and beverages during the Easter period. Meanwhile, investor sentiment hit its highest level since nearly a decade. According to Sentix sentiment rose to 28.4 in June from 27.4 in May.

In the U.K., a former key advisor to David Cameron has called on the Conservative leader Theresa May to resign given her role in police cuts when she led the Home Office. The comments come only a few days before U.K. voters choose a new Parliament.

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