Brexit: NI issues on table as talks resume in Brussels
Brexit negotiations resume in Brussels on Monday with Northern Ireland issues expected to be discussed on Wednesday.
After the last round of talks, the EU's chief negotiator said more work needed to be done to protect cross-Irish border co-operation.
Michel Barnier also said the UK should clarify how it intends to maintain the common travel area (CTA) between the UK and Ireland.
Since then the UK has published a position paper on Northern Ireland.
It attempts to tackle those issues.
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The paper's firmest proposals concern the operation of the CTA.
It is a bilateral UK-Ireland arrangement that has existed since 1922 and allows for free movement of UK and Irish citizens between the Republic of Ireland, Northern Ireland and the rest of the UK.
It also allows Irish and UK citizens to access various services and benefits in each country such as the right to work, access public services and vote in certain elections.
The paper says the UK can provide "a clear assurance" that the CTA can continue to operate without "compromising in any way Ireland's ability to honour its obligations as an EU member".
It adds that the UK would be content for such an assurance to be reflected in the withdrawal agreement.
The paper deals with the cross-border bodies, which were created as a result of the Good Friday Agreement, in a more limited way.
It focuses mostly on the Special EU Programmes Body, the organisation which distributes so-called peace funding.
It also discusses options for future cross-border trading arrangements and how a hard border could be avoided.
However, the EU appears unhappy that the UK is trying to introduce trading arrangements into the Northern Ireland discussions.
EU members have agreed that a trade deal will not be discussed until the "separation issues" of migrant rights, a financial settlement and the Irish border have been agreed.
On Friday, senior EU officials used a media briefing to warn the UK not to use the Northern Ireland peace process as a "bargaining chip" in the negotiations.
They also dismissed some of the ideas for trying to create a frictionless border as "magical thinking".
A spokesman for the Department for Exiting the EU said: "We have always been clear about the importance we attach to Northern Ireland and the Good Friday Agreement.
"There have been decades of progress to achieve peace in Northern Ireland which is why the UK has put forward a detailed position paper that puts protecting the Good Friday Agreement at the heart of our approach.
"That includes a proposal that the UK and EU should agree upfront on the crucial importance of avoiding a hard border for the peace process in Northern Ireland."