Protesters hold a flag and a placard outside the Houses of Parliament, in front of a statue of Winston Churchill, in London, Britain on Jan. 15. 2019. The British parliament on Tuesday rejected overwhelmingly the Brexit deal, further complicating the country's historic exit from the European Union (EU). (Photos: Xinhua)

Pro-Brexit and anti-Brexit protesters hold flags and placards outside the Houses of Parliament, in London, Britain on Jan. 15. 2019. The British parliament on Tuesday rejected overwhelmingly the Brexit deal, further complicating the country's historic exit from the European Union (EU).

Pro-Brexit protesters hold flags and placards outside the Houses of Parliament in London, Britain, on Jan. 15. 2019. A delayed parliamentary vote on the Brexit deal is scheduled to take place on Tuesday.

Protesters gather outside the Houses of Parliament, in front of a statue of Winston Churchill, in London, Britain, Jan. 15. 2019. The British parliament on Tuesday rejected overwhelmingly the Brexit deal, further complicating the country's historic exit from the European Union (EU).

Anti-Brexit protesters hold flags outside the Houses of Parliament in London, Britain, on Jan. 15. 2019. A delayed parliamentary vote on the Brexit deal is scheduled to take place on Tuesday.

Pro-Brexit and anti-Brexit protesters hold flags and placards outside the Houses of Parliament in London, Britain, on Jan. 15. 2019. A delayed parliamentary vote on the Brexit deal is scheduled to take place on Tuesday.

Pro-Brexit protesters hold placards outside the Houses of Parliament in London, Britain, on Jan. 15. 2019. A delayed parliamentary vote on the Brexit deal is scheduled to take place on Tuesday.

Pro-Brexit protesters hold flags and placards outside the Houses of Parliament in London, Britain, on Jan. 15. 2019. A delayed parliamentary vote on the Brexit deal is scheduled to take place on Tuesday.

Pro-Brexit and anti-Brexit protesters hold flags and placards outside the Houses of Parliament in London, Britain, on Jan. 15. 2019. A delayed parliamentary vote on the Brexit deal is scheduled to take place on Tuesday.