What are Theresa May's customs options?
A customs partnership and maximum facilitation are the two main Brexit trade options under consideration.
Monday 16 July 2018 13:18, UK
The Prime Minister is fighting to reconcile warring Brexiteer and Remainer factions within the government over customs arrangements with the EU after Brexit.
Brexiteers, who have given Theresa May an ultimatum, argue any strong partnership is a betrayal of the people's will, whereas Remainers say it's the only solution to the Irish border issue.
The Prime Minister has two main options - although the EU would need convincing of either.
:: A customs partnership
An option favoured by Remainers, goods coming to Britain would be electronically tracked by British officials.
Firms selling to the UK would have to pay the same tariff as if their goods were headed to the EU. This money collected would be sent on to Brussels.
If the UK sets a trade tariff below that of the EU, companies would have the difference refunded.
It is likely EU countries would have to track goods destined for the UK at their borders in order for the system to work.
The partnership would in theory allow the UK to leave the customs union and negotiate free-trade agreements with non-EU countries. Brexiteers say the UK would still effectively be in the customs union and it would be more difficult to freely negotiate worldwide deals.
It would also remove the potential need for a physical EU-UK customs borders between Northern Ireland and the Republic of Ireland. Some argue that even a technological border is enough of a presence to contravene the Good Friday Agreement.
:: Maximum facilitation
A plan that would potentially dramatically reduce customs controls and barriers between the UK and the EU.
Favoured by Brexiteers, goods would be electronically tracked and pre-cleared with tax authorities.
A 'trusted trader' scheme would be employed to allow firms to move goods without having to pay duty every time their goods crossed the border.
This option would be more bureaucratic than if the UK stayed inside the customs union - but supporters argue it would guarantee that Britain would be able to complete deals with non-EU nations as the UK would no longer have to comply with EU tariff regulations.
This plan requires new infrastructure at foreign ports such as Calais, the Netherlands and Sweden. This could risk significant backlogs of traffic at UK ports.