Senior European Union officials have warned Britain not to use the Northern Ireland peace process as a bargaining chip in the Brexit negotiations.

In a briefing to media in Brussels this afternoon, officials expressed concern that in the UK’s recent position paper on Ireland there are specific examples where London is attempting to link Irish issues with the future trade relationship between the UK and the EU, which is off-limits, according to the EU's timetable.

"The peace process must not become a bargaining chip in these negotiations," said one senior official.

While officials have welcomed aspects of the British paper on Ireland, they also said it was "full of magical thinking."

Officials also said that the EU’s position on Brexit and that of the Irish Government were "indivisible".

Echoing much of the Irish Government’s recent rhetoric on Brexit and its impact on the Irish border, a senior official said: "The position of the Irish Government, the other 26 member states and the institutions is indivisible. It is the same position.

"We agree… technical [solutions] cannot outpace the political. We are not yet there in terms of the political debate and the full realisation of the implications of the UK withdrawal on Ireland."

These are perhaps the strongest statements yet by the EU on Britain’s approach to Ireland in the Brexit negotiations.

The UK, said one official, had to take responsibility for Brexit and how it affected Ireland.

"The decision to leave the EU was the UK’s decision," said the official. "It was not the decision of Ireland. It was not the decision of the EU.

"So the UK has to take responsibility for the impact of that. In that respect, the uniqueness of the situation and the creativity of the solutions that the European Council has referred to (which will be required): that must not be a burden on the EU side."

In terms of using Ireland as a bargaining chip to advance its interests, one senior EU official drew attention to two elements of the UK’s position paper.

One is the reference to how to manage agri-food and animal health regulations, the other is the reference to the continued funding of the EU’s PEACE programme.

Officials say both these areas stray into the nature of Britain’s future trading relationship with the EU.

According to the phased approach to the negotiations, agreed by all 27 governments in their Negotiating Guidelines in April, the EU will only get into the future relationship once they have confidence that Britain will agree to meeting its financial obligations on withdrawal, to ensuring the rights of EU citizens living in the UK (and vice versa) and the issue of the Irish border.

One senior EU official said: "They say we can resolve agricultural issues by having a mutual recognition of the standards between the EU and the UK.

"Similarly, they say that they want the PEACE programme to continue, with EU funding, but without having a broader discussion about what parts of the existing [funding] commitments they will stand by.

"Even when they say that they want the PEACE programme to continue, within that there are certain remarks about the governance which differs from the existing governance. These are linkages which are made – between the question of Ireland and Northern Ireland – and the question of the future relationship and other aspects of the withdrawal agreement. And that’s something which we’ve strenuously avoided."

The British Government has argued that resolving the Irish border question necessitates a discussion of the future trade relationship, and future customs arrangements.

The EU accepts that, but it insists that the UK must go deeper into how it intends to preserve the peace process, and in particular into how it will bullet-proof North South co-operation from Brexit.

The Irish Government privately believes the UK limits its attitude to the North South strand of the Good Friday Agreement to issues such as energy co-operation, and the EU appears to agree with this critique.

"On the big headline objectives," said one EU official, "preserving the Good Friday Agreement, the Common Travel Area, there is agreement.

"But - and I think this is something the UK recognised in the last round of negotiations – how to preserve that requires more thinking.

"The UK mentions the example of the Single Electricity Market (SEM). How can you do that outside the EU and outside the Single Market given that the UK has decided to leave the SM?

"What we are missing is a similar level of awareness on all the [other] areas of North South co-operation. We have 12 [North-South] policy areas, many of them are underpinned by EU law.

"We need to hear from the UK how are they going to preserve the working of the [North-South] institutions, and their ability to work on substance in the absence of an EU law framework.

"We will have to go a lot more deeply into this this time around. The border is not just an economic issue, it is a societal and a political issue."

A decision will be taken at the European Council meeting on 19 and 20 October as to whether or not enough progress has been made on the divorce negotiations to merit a start to the future trade negotiations.

The third round of negotiations will begin next week in Brussels.

Britain’s Brexit Secretary David Davis is expected to argue on Sunday that the EU should adopt a more "flexible" approach to the negotiations, in other words, to start the future relationship discussions quickly.

That is likely to be rebuffed by the EU27.

The British side has published a flurry of position papers in the past two weeks, but they have by and large been poorly received by the European Commission Task Force under Michel Barnier, and by member states.

There is a growing suspicion that the EU27, including Ireland, will not be in a position to move to the second phase of negotiations by the time the October summit comes around.

A spokesman for Britain's Department for Exiting the European Union said: "We have always been clear about the importance we attach to Northern Ireland and the Good Friday Agreement - and to the lives and livelihoods of the people of Northern Ireland.

"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.

"We also set out the importance of preserving North-South and East-West co-operation under the Good Friday Agreement, which covers a range of areas of economic and political collaboration.

"We look forward to the Commission setting out its position and response to these proposals."