European markets closed lower on Friday ahead of a proposed referendum of pro-Russian Ukrainians this weekend, despite Russian President Vladimir Putin calling for it to be postponed.
The pan-European FTSEurofirst 300 Index closed provisionally down 0.3 percent at 1,354.93 points. It comes after the index hit a 2014 peak of 1,359.07 points on Thursday, its highest level in around 6 years.
The euro also continued to slide against the dollar on Friday, after European Central Bank President Mario Draghi on Thursday hinted at policy action next month.
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President Putin landed in the Crimean city of Sevastopol on Friday to celebrate Victory Day. During the visit, Putin said Russia had become stronger with the addition of Crimea.
"I am sure that 2014 will go into the annals of our whole country as the year when the nations living here firmly decided to be together with Russia, affirming fidelity to the historical truth and the memory of our ancestors," Putin said in a brief speech, according to Reuters.
It came as Ukrainian interior minister, Arsen Avakov, said that security forces had killed around 20 pro-Russian rebels in Mariupol, in what looks to be a significant move by Kiev to try and end the insurgency in the east of the country.
Pro-Moscow rebels in the region have planned a referendum on Sunday, following on from Crimea's vote to break away from Ukraine.
Meanwhile, credit ratings agency Standard & Poor's upgraded its outlook for Portugal to stable from negative. This failed to boost the Portuguese benchmark PSI20 however, which closed down 1.8 percent.
In the U.S., stocks opened in mild decline on Friday, with the Nasdaq Composite on track for weekly losses, after chip manufacturer Nvidia reported quarterly results and joined the technology shares on the decline.
Asian stocks were mixed on Friday following a subdued Chinese consumer price inflation report and as traders also kept a close eye on Ukraine. Japanese shares reversed early losses to rise above 14,200 points, extending with gains for a second day. Still, the benchmark Nikkei posted a 1.8 percent fall for the week.
Steel giant reported first-quarter core profit in line with analyst forecasts on Friday, but cut its forecast for global steel use. The stock closed down 3.7 percent.
In other corporate news, the mega-merger of advertising giants and was called off on Thursday night. Shares in Publicis closed down around 0.9 percent following the news.
Shares in closed down around 2.6 percent after the company posted a 23 percent fall in first quarter net profits, missing market expectations.