Boris Johnson will speak with European Commission president Jean-Claude Juncker on Wednesday afternoon to discuss his proposals for changing the backstop.
The UK is due on Wednesday to submit its formal plans for altering the Northern Ireland backstop in a bid to secure a deal with the European Union.
The Prime Minister has vowed to remove the backstop “whole and entire” and his team has been working behind the scenes on ways of revising the terms originally agreed by his predecessor Theresa May.
Mr Johnson is set to brief Mr Juncker on his ideas during a phone call at 4.15pm and his European adviser David Frost will also hold technical talks with Brussels’ negotiating team, the European Commission has confirmed.
Mina Andreeva, the commission’s chief spokeswoman, said: “We understand that we will receive a text from the United Kingdom later today and once received we will examine it objectively and in light of our well-known criteria.
“We will listen very carefully to the United Kingdom.”
The PM will also hold a blitz of conversations with European leaders after his backstop proposals have been published.
Downing Street confirmed Mr Johnson will spend the afternoon on the phone once his plans for reshaping the Northern Irish backstop have been released.
The papers are expected to be published before 4pm.
Under the Withdrawal Agreement negotiated by Mrs May, if there was no long-term trade agreement in place by Brexit day that ensured an open border, the whole of the UK, including Northern Ireland, would remain closely tied to EU rules and its customs union.
But according to a briefing received by The Daily Telegraph, Mr Johnson wants to make wholesale changes to that agreement which would effectively create two borders between the UK and Ireland.
The UK would remain closely tied to the EU’s rules during a transition period ending in 2021 and then enter a free trade agreement with the bloc, said the report.
After that, in a plan that has been dubbed “two borders for four years”, Northern Ireland would be kept in a special status until 2025, leaving the EU customs union alongside the rest of the UK, but remaining aligned on all single market rules for agriculture and industrial goods.
Ms Andreeva said she would not “pre-empt any reaction” from the EU before senior figures had a chance to study the details.
“We want to enter into constructive discussions, so I will certainly not pre-empt any reaction here before even having received the text,” said the spokeswoman.
She added: “The EU wants a deal. We think an orderly withdrawal is far more preferable than a no-deal scenario.
“And in order for there to be a deal, we must have a legally operable solution that meets all the objectives of the backstop preventing a hard border, preserving the north-south co-operation and the all-Ireland economy, and protecting the EU’s single market and Ireland’s place in it.”
The commission confirmed Mr Juncker was likely to discuss the Brexit developments in a phone call with German Chancellor Angela Merkel on Wednesday.
“They will discuss all topical issues, so I assume that Brexit will feature in terms of topical issues discussed,” Ms Andreeva told journalists in Brussels.