BERLIN (Reuters) - Britain is sticking to its plans for a post-Brexit border between its province of Northern Ireland and EU member Ireland, the country’s Brexit minister was quoted as saying after signals from the EU that it was open to new ideas.

Britain's Secretary of State for Exiting the European Union Dominic Raab arrives at Downing Street in London, Britain, September 13, 2018. REUTERS/Hannah McKay

The United Kingdom is due to leave the EU in March next year, and so far no comprehensive agreement has been reached. One of the most difficult problems is how to avoid a hard border between Ireland and Northern Ireland.

Britain’s Dominic Raab told several European media outlets, including Germany’s Spiegel Online, that Prime Minister Theresa May’s economic and trade policy plan which would allow goods to cross the UK-Irish border was the only credible proposal.

“These are so far the only proposals that guarantee smooth trade between Britain and the EU and take account of the specific problems in Ireland. I have seen no other credible alternative, either from here or from the EU side,” Raab was on Tuesday quoted by Spiegel as saying.

He also said Britain will stick to its position that it will not allow a customs border to be established down the Irish Sea between it and Northern Ireland.

“Our position remains that we couldn’t see a customs border down the Irish Sea and that the economic and the constitutional integrity of the United Kingdom needs to be respected,” he told the Irish Times newspaper.

However, he said they would listen to other suggestions.

“What I’m not going to do is prevent or say that we will not entertain any proposals, at least to consider in relation to anything, because actually we ought to be trying to at least listen to what the other side is saying,” he added.

The EU’s chief Brexit negotiator Michel Barnier said earlier this month the bloc was open to discussing different ways of checking goods crossing the UK-Irish border, including technical checks on board vessels or in ports outside Ireland.

Both the EU and Britain want to avoid a hard border between UK’s Northern Ireland and the Irish Republic as such a move could undermine a 1998 peace agreement that ended decades of sectarian conflict in the north.

It is, however, unclear how goods crossing between the EU and the UK in Ireland would be monitored if there was no border and if Northern Ireland, as a part of the UK, leaves both the customs union and the single market.

Raab said the upcoming EU meeting in Salzburg, Austria, would be an “important milestone”.

“We have already made extensive compromises.. We have shown ourselves to be very pragmatic and ambitious. Now the ball is in the European Union’s court,” Raab was quoted in Spiegel as saying, added there would be no second referendum on Brexit.

If lawmakers in parliament were to vote down any agreement, then there would probably be no deal.