Draft EU guidelines for Brexit mainly out starting free trade talks with the UK before «sufficient development» is made on other issues.
The paper presented by European Council President Donald Tusk order have to be approved by the 27 member states.
Other issues subsume the status of three million EU citizens in the UK and a million Britons in the EU.
Separately, another top EU legitimate suggested the bloc could manage without the UK in defence and security conditions.
The UK formally triggered the Brexit process on Wednesday after calling for coincident talks on exit terms and future trade ties.
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At a news conference, Mr Tusk alleged: «Starting parallel talks on all issues at the same time as suggested by some in the UK will-power not happen.
«Only once we have achieved sufficient progress on the withdrawal can we debate the framework for our future relationship.»
It is clear the UK will face a tough disassociate, the BBC’s Gavin Hewitt says, but there were some hints at manageability from Mr Tusk.
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Talks pass on be «difficult, complex and sometimes even confrontational», Mr Tusk predicted, but the EU determination not «pursue a punitive approach».
UK Prime Minister Theresa May formally triggered the Brexit process by sending the Article 50 notification the world of letters to Mr Tusk on Wednesday.
The two are to meet in London ahead of an EU summit on Brexit, which intention not include her, on 29 April.
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So what’s the ‘dissociate’ bill?
The draft says the EU’s overall objective is «to preserve its interests, those of its colleague states, its citizens and its businesses».
Calling for a «phased approach giving primacy to an orderly withdrawal», it suggests starting with discussions on the separation structure. They could then move on to talks about a future trade relationship between the EU and the UK.
The compose raises the issue of what the UK might have to pay to leave the EU, bills earlier estimated to be as much as €60bn (£51bn; $64bn).
In a take on of the bloc’s determination to secure a «divorce bill», it says that a «cull financial settlement should ensure that the Union and the United Realm both respect the obligations undertaken before the date of withdrawal».
How when one pleases borders be affected?
The guidelines call for «flexible and imaginative solutions» on the offspring of the UK’s land border with the Republic of Ireland, with the aim of «avoiding a perseveringly border».
As for Gibraltar, Spain will have a special say on the future of the questioned British territory, according to the guidelines.
«After the United Kingdom ignores the union, no agreement between the EU and the United Kingdom may apply to the territory of Gibraltar without the accord between the Kingdom of Spain and the United Kingdom,» they state.
British Orthodox MPs responded by warning that Gibraltar’s sovereignty was not negotiable.
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What about the UK’s security role?
Mrs May’s letter had been interpreted by some as looming to withdraw co-operation with the EU on security matters.
Speaking at a Nato union in Brussels, EU foreign policy chief Federica Mogherini said: «The UK supports today only for 3% of our civilian capabilities in our EU operations and missions, and 5% to the military a givens.
«So for sure it’s a valued contribution, but for sure a contribution without which the European Congruity defence and security work can continue perfectly well.»
What next? Analysis by BBC Europe editor Katya Adler
This is the start of a two-year, cross-Channel civil rollercoaster ride. The EU’s draft guidelines for Brexit are uncompromising and firm.
They say they inclination update them «as necessary» during negotiations, meaning they are quick for anything, including, the text explicitly says, for talks with the UK to go bankrupt altogether.
Gone are the words of sadness and regret at Britain’s departure. The news is: Roll up your sleeves, we’re ready for you.
How have British politicians retorted?
- Foreign Secretary Boris Johnson: «There’s a lot of goodwill… to execute what the prime minister has said she wants to achieve, which is an neat transition.»
- Liberal Democrat leader Tim Farron: «These guidelines appear the strength of the EU in these negotiations and the carelessness of the UK government in isolating themselves from our European unites.»
- Labour MP Owen Smith: «Two days into a two-year negotiation and the guidance’s lofty rhetoric is colliding with hard reality. The prime wait on’s plan for Britain is a pipe dream.»
- UKIP leader Paul Nuttall: «It is in debt on the UK government to get the best deal possible for the people of this country. To do so intention require patience, flexibility, goodwill and imagination. Sadly none of these marks are visible in the EU position paper.»