European stocks closed lower on Wednesday, as political events on both sides of the Atlantic weigh on investor sentiment.

The pan-European Stoxx 600 was 0.7% lower at the end of the session, with technology stocks leading losses on a 1.2% decline as almost every sector and all major bourses traded in the red.

Market focus was largely attuned to news of a bid from Democrats in the U.S. House of Representatives to impeach President Donald Trump.

The impeachment inquiry was announced by House Speaker Nancy Pelosi on Tuesday, and follows concerns over Trump's efforts to push Ukraine to investigate the family of Democratic presidential hopeful Joe Biden.

The White House published a summary of a call between Trump and Ukraine's President Volodymy Zelensky which revealed the U.S. leader asked Zelensky to "look into" former Vice President Biden's son.

President Trump told the United Nations General Assembly on Tuesday that he would not accept a "bad deal" in trade negotiations, while China's top diplomat said Beijing would not be threatened or allow interference in its affairs.

Stateside, stocks dipped after that release but traded higher on the back of Trump's hint of fresh hopes for a trade deal between the U.S. and China.

Back in Europe, Brexit uncertainty continues to cloud markets. U.K. Prime Minister Boris Johnson was dealt a serious defeat Tuesday after Britain's Supreme Court ruled his decision to suspend Parliament weeks ahead of Brexit was unlawful.

Johnson disagreed with the verdict and said he would take the U.K. out of the EU by an Oct. 31 deadline. He has faced increased calls from lawmakers to resign following the ruling. MPs reconvened in parliament on Wednesday, with opposition lawmakers buoyed by the decision but split on the best approach to Brexit from here.

In corporate news, Deutsche Bank's Frankfurt offices were visited by German authorities on Wednesday seeking information in relation to Danske Bank, prosecutors said. The German lender's stock ended the session 0.5% higher.