The EU's chief Brexit negotiator has said talks on Britain's exit will not be concluded "quickly and painlessly".

Michel Barnier said it was an "illusion" to think this was the case, as he set out the European Commission's detailed negotiating guidelines for the first phase of withdrawal talks.

He said: "Some have created the illusion that Brexit would have no material impact on our lives or that negotiations can be concluded quickly and painlessly. This is not the case.

"We need sound solutions, we need legal precision and this will take time."

EU negotiator lays out 'phase one' Brexit points

It comes amid reports Britain could be hit with a €100bn (£84.5bn) "divorce bill", a sharp increase on previous estimates of €60bn.


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Speaking in Brussels, Mr Barnier said the opening phase would focus on the financial settlement, the status of expatriate citizens and the future border between the UK and EU in Ireland.

The French politician warned the talks would be complex and would have "consequences" for people's lives.

Mr Barnier stressed the so-called divorce bill was not a punishment for the UK leaving, but rather a "settling of accounts" that needed to happen before talks could progress.

"The UK must put a great deal of energy and effort into these three issues over the next weeks and months and that will increase the chances of making a deal," Mr Barnier said.

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He said he hoped to be in a position by October or November to reach a view on whether sufficient progress has been made to move to the next phase, involving talks on future trade arrangements.

In order to do this, Mr Barnier said the EU would need "clear commitments", rather than "window dressing" on the three issues.

This will involve things like agreements on issues like the cut-off date for EU citizens to keep rights in the UK, as well as the nature and duration of those rights, and a "specific methodology" for calculating the UK's liabilities, he said.

Agreements reached at this stage should be final, Mr Barnier said, to avoid starting the next phase "in a climate of mistrust and uncertainty".

Talk of bad Brexit talks is 'Brussels gossip'

Relations between London and Brussels have appeared to enter a rocky patch, amid claims a recent Brexit dinner involving Mrs May and Jean-Claude Juncker was a disaster.

Mr Barnier, who was at the talks, said in response to a question from Sky's Europe Correspondent Mark Stone that the gathering was "very cordial" - and revealed he, like the PM, loves hiking.

And it was this shared passion that he used as the basis for analogy about the road ahead.

"If you like walking in the mountains you have to learn a certain number of rules," Mr Barnier said.

"You have to learn to put one foot in front of the other because sometimes you are on a steep and rocky path.

Will a shared love of walking clear the Brexit path?

"You also have to look at what accidents might befall you - falling rocks.

"You have to be careful to keep your breath, you have to have stamina because it could be a lengthy path.

"And you have to keep looking at the summit, the outcome. That's what I learnt when mountain-walking."

Britain triggered Article 50 - the formal process for leaving the EU - in March, starting a two-year negotiating process.

Mr Barnier hopes to wrap up the talks by October 2018 to get the final deal passed by the European Parliament and in time for Britain's scheduled departure on 29 March 2019.