Northern Ireland would remain part of Europe’s single market but Britain would leave it. There would be regulatory checks down the Irish Sea but not at the Irish border. Europe will demand a dropping of the DUP veto and something near to the backstop on the customs union. There was therefore a self-evident inconsistency between that commitment and the commitment to leave the single market and customs union. But the government also gave a commitment to the DUP that Northern Ireland would be treated the same.

Source: The Guardian October 05, 2019 19:52 UTC