EU Exit Negotiations

We all hope that the Government find a form of words that enables the negotiations to move on to phase 2, but do they not have to realise that the reason why there is this problem is because of their decision to leave the customs union and the single market? Given that the leader of the Scottish Conservatives and the Mayor of London have both suggested that whether it is convergence or no divergence, it should be applied to the whole of the United Kingdom, is it not time for the Government finally to recognise that they need to make a different decision if they are to avoid the imposition of a hard border in Northern Ireland?