UK government to unveil post-Brexit border plan on Wednesday
The government has said a temporary customs union could be put in place at the UK's borders after Brexit.
Brexit Secretary David Davis will ask for an interim period as part of the negotiations with Brussels.
A series of papers is being published this week.
On Wednesday, the UK government will set out its ideas for the border between Northern Ireland and the Republic of Ireland.
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Slowly detail is emerging of what life could be like after Brexit.
Three ideas are mooted.
One proposal suggests a customs arrangement in which the UK would manage a new customs border with the EU.
Another proposes a new partnership with the EU, which would negate the need for a customs border.
The other suggestion is a temporary customs union.
That would allow the UK to develop procedures and put in place appropriate technology and also give businesses more time to adjust.
A third round of negotiations is due to take place in Brussels at the end of the month.
A spokesperson for the Irish government said it welcomed "indications that the UK is providing more clarity on its thinking".
"The UK's position paper on future EU-UK customs arrangements will be analysed in detail along with our EU partners," the spokesperson said.
"The paper is directed at the EU as a whole and will need careful consideration by the commission and all 27 EU member states."
Earlier this week, the chancellor and the international trade secretary said the UK definitely would leave both the customs union and the single market when it exits the EU in March 2019.
In a joint Sunday Telegraph article, Philip Hammond and Liam Fox said a "time-limited" transition period would "further our national interest and give business greater certainty" - but warned it would not stop Brexit.
Earlier this month, Irish Prime Minister Leo Varadkar called for "unique solutions" to preserve the relationship between the UK and the European Union after Brexit.
On his first official visit to Northern Ireland, he raised the possibility of a bilateral UK-EU customs union.
The taoiseach described Brexit as "the challenge of this generation".
In response, the UK government said it wanted a special partnership with the EU, including an "ambitious free trade agreement and a customs agreement".