London, UK. 9th January, 2019. Police officers observe rival protests by activists from pro-Brexit group Yellow Vests UK and anti-Brexit group SODEM (Stand of Defiance European Movement) outside Parliament on the first day of the debate in the House of Commons on Prime Minister Theresa May's proposed Brexit withdrawal agreement. Policing arrangements outside Parliament have been strengthened following complaints regarding harassment of MPs by Yellow Vests UK organisers.