The backstop must not lead to diminished UK sovereignty in NI

Tories from the prime minister down have ruled out an Irish Sea border. This week that included Philip Hammond, who is seen as a Brexit sceptic.

The chancellor even told this newspaper that it was taking time for the EU to realise UK adamance on that point.

This is welcome, but Mr Hammond also said the UK was fully committed to the ‘backstop’, as Theresa May did in Belfast the week before. What this means in practice remains unclear, because the backstop (to prevent a hard land border) is not finalised and is interpreted differently.

One thing though is clear. Britain foolishly committed to no infrastructure at the land border. No-one wants checks and it should have agreed that in outline, but the UK should not write into law anything that diminishes sovereignty on its territory up to and including the border. Even the moderate Lord Alderdice has queried the wisdom of any bar on security checks impossible if ever needed.

London is talking sense on no internal border but must also have control of its external frontier, including CCTV.

Note how today the department in charge of Brexit when we asked about this has given greater reassurance to nationalists and Dublin than to unionists, by emphasising that there will “never” be border infrastructure. Why not tell us the right to have infrastructure will always remain?