According to The Telegraph, the plan specifically aims to keep Northern Ireland in the EU's internal market until 2025 after the rest of the UK leaves the Union. This means that an EU border will be drawn in the Irish Sea.

At the same time, customs checks will also be established between Northern Ireland and Ireland, The Guardian reports.

According to Swedish Radio, Boris Johnson should already have received first approval for his border proposal by the Northern Ireland Party DUP, which supports the current government in a parliamentary cooperation since 2017.

Ireland opposed the proposal

Ireland's Foreign Minister Simon Coveney judges the rumored proposal.

- We haven't seen this yet. But if the reports we read are true, it does not appear to be a basis for any agreement, that is one thing that is certain, says Somon Coveney to the Irish television channel Virgin Media One.

Ireland has previously opposed the proposal for customs controls as it considers that new violence could arise at the border with Northern Ireland as well as within the country.

For the UK, tariffs would mean that the country could start negotiating with other countries such as the United States on a new free trade agreement and at the same time no longer remain in the EU's regulatory system.