Michael Gove is concerned the EU will use the Northern Ireland border issue to “hold us hostage” and keep the UK in the Single Market and Customs Union.

The Environment Secretary raised concerns at a private dinner of Tory Eurosceptics that Britain may be unable to secure a customs deal with Brussels before it leaves the EU in March 2019.

He believes that the EU’s Irish border “backstop” could be used as a “Trojan Horse” during negotiations in the 21-month transitionperiod after Brexit to keep Britain in the Customs Union indefinitely.