Cross-party MPs attend an event about opposing the suspension of parliament to prevent a no-deal Brexit and sign the Church House Declaration in London, Britain, August 27, 2019. /VCG Photo

Over 160 MPs have signed the declaration to support stopping a no-deal Brexit "using whatever mechanism possible." / VCG Photo

(From left) Green Party MP Caroline Lucas, Liberal Democrat leader Jo Swinson, Plaid Cymru Commons leader Liz Saville Roberts, SNP Westminster leader Ian Blackford, shadow chancellor John McDonnell and Change UK leader Anna Soubry were all at the ceremony. / VCG Photo

The United Kingdom is heading toward a constitutional crisis at home and a showdown with the European Union as Prime Minister Boris Johnson has pledged to leave the bloc on October 31 without a deal. / VCG Photo