Theresa May laid out 12 negotiating objectives in her first detailed speech on the government’s approach to Brexit since the referendum six months ago Times photographer Jack Hill

Theresa May warned Brussels yesterday that any attempt to punish Britain for leaving the EU would be “an act of calamitous self-harm” as she set out her Brexit vision for the first time.

Taking a tough stance before exit negotiations begin, the prime minister insisted that she would walk away from the talks if offered a bad deal. Britain could lower tax rates to lure businesses from the Continent, she warned, while a lack of flexibility from Brussels risked “crushing into tiny pieces” the EU project.

Mrs May called on the EU to wrap up a separation agreement and new trade deal within the next two years. She confirmed that Britain would leave the single market, strongly hinted at a cap on European migrants and…