Growing concern among Brexiteers over 'exploitation' of Irish border

Is the Irish border problem being used to frustrate Brexit? That’s the claim made by the Foreign Secretary this morning. After Sky News published an excerpt of a letter Boris Johnson wrote to the Prime Minister in which he appeared to concede that physical infrastructure at the border post-Brexit was an option, Johnson gave a breakfast interview (straight from his run) to try and clarify his comments. Johnson insisted the letter he wrote was ‘very good’ (and said he looks forward to publishing it in full) but warned that the border issue was being exploited by those who wish to frustrate Brexit:

‘What is going on at the moment is that the issue of the Northern Irish border is being used quite a lot politically to try and keep the UK in the customs union – effectively the single market – so we cannot really leave the EU. That is what is going on.’