Leaders from the three main political parties in Westminster arrived in Scotland on Wednesday to campaign to keep the country in the United Kingdom. The pro-independence vote in Scotland has been gaining ground as the referendum looms next Thursday.
"With the nationalist and unionist campaigns neck-and-neck ahead of next week's referendum, financial questions are being raised which are proving hard for the markets to side-step," Daniel Sugarman, a market strategist at ETX Capital, said in a research note on Wednesday.
Read MoreHow a Scottish exit could hit Britain's wealthy
Telefonica Deutschland tanks
Telefonica Deutschland plummeted around 22 percent to the bottom of benchmarks on Wednesday, with the company going ex-dividend and Barclays cutting its price target for the stock.
FTSE 100-listed SportsDirect closed down around 1.7 percent trade, after reporting that first-quarter sales at its fashion and brand divisions fell.
Also in the U.K., Kingfisher posted a flat profit for its latest quarter, but shares closed around 4.3 percent higher after the retail group unveiled new CEO Veronique Laury.
Similarly, shares of Fiat closed around 1.9 percent higher on the news that Luca Cordero di Montezemolo will step down as chairman of Fiat-subsidiary Ferrari and be replaced by Sergio Marchionne.
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