There is no need for us to leave the EU with all the consequent complications. We can achieve the objectives of the referendum (sovereignty and immigration) in a much simpler way: (1) Remain in the EU. (2) Declare that the European court of justice no longer has jurisdiction in the UK – UK law is supreme. (3) Say that because of the crowds at the frontier and the increasing danger of terrorism, we are obliged, as a temporary measure, to introduce visas for EU citizens travelling to the UK.

Then wait and see how the EU reacts. There will be a lot of huff and puff. Some member states may follow and do the same. If, finally, some penalties are imposed they will surely cost a lot less than Brexit. We can set and vary the visa conditions later, maintain the requirement or remove it at any stage – and some countries could be quietly exonerated.

Francis Farley

Visiting professor, University of Southampton

• You report (13 December) the House of Lords committee on Brexit’s argument that the process of withdrawal from the EU will be hard and damaging, but focus mainly on tariffs. Philip Hammond and Peter Lilley did the same in answering questions on the Radio 4 Today programme on Tuesday morning. But the difficulty does not lie with tariffs so much as with regulations and product standards, which pro-Brexit politicians have either ignored or been naively over-optimistic about. We need a carefully managed trade relationship with the EU during and after any transition period. This means product standards not just for final products (cars, washing machines, electronic goods, machine tools) but for all the stages of the supply chain. Mutual recognition between the UK and EU will deal with some of this; but only some. Tariffs threaten relatively small increases in costs, except, as your figures show, in agriculture. Scrapping agreed product standards risks unpicking supply chains built up over 40 years which are now the core of much of our industry.

Chris Farrands

Nottingham

• Your editorial (12 December) addresses the problems that Brexit has brought to Northern Ireland and the Irish Republic. There is a very simple solution that sane people in the UK and Ireland would embrace. Northern Ireland, which voted to remain in the EU, should join the Irish Republic. This gets rid of the border problem. To allow citizens of “New Ireland” to travel and work freely in the UK, as now, they could be given dual citizenship with a UK passport as well as an Irish passport. The UK could also give them tariff-free trade. All the Irish people would get everything they want. A few people might miss having the Queen as head of state, but this is surely a small price to pay for all the benefits, including peace. If it really worries them, they could go to the New UK to live.

Trevor Randall

Great Missenden, Buckinghamshire

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