Theresa May was battling to save her Brexit deal and her own position as prime minister on Thursday after a series of ministerial resignations and the threat of a Eurosceptic coup left the Conservative party on the brink of civil war.

Mrs May insisted she would stick to her plan, which would keep Britain closely tied economically to the EU, and said she was not about to quit in spite of growing criticism from Brexiters in her own party.