Theresa May's Brexit challenge was laid bare for all to see today as European leaders gave her the cold shoulder at a key EU summit in Brussels.

As the other 27 heads of state hugged and kissed ahead of the meeting, the British Prime Minister was left with no one to talk to.

Mrs May was left awkwardly fidgeting with her cuffs. After 11 seconds of looking around for someone to talk to, she gave up and took her seat at the table.

After 11 seconds of looking around for someone to talk to, Theresa May gave up and took her seat at the table

The Prime Minister was left awkwardly fidgeting with her cuffs as other EU leaders hugged and kissed around her

To many it symbolises the EU's attitude towards Britain following the decision to leave the EU in June.

EU leaders even excluded Mrs May from their dinner tonight so they can discuss their Brexit plans in secret.

The session involving the UK Prime Minister won't even address Brexit and will instead focus on the migration crisis.

Mrs May's message to her hostile European counterparts today was that a 'smooth and orderly Brexit' was in everyone's interest.

She made the warning after it emerged that Sir Ivan Rogers, Britain's ambassador to the EU, has warned the Government that finalising a trade deal with the EU could take 10 years.

Theresa May's Brexit challenge was laid bare for all to see today as European leaders gave her the cold shoulder at a key EU summit in Brussels

To many it symbolises the EU's attitude towards Britain following the decision to leave the EU in June

After 11 seconds of looking around for someone to talk to, she gave up and took her seat at the table

He reported the views of Brussels officials and other EU leaders to Downing Street in October, the BBC said.

The startling claim emerged just a day after Brexit Secretary David Davis told MPs a short 18 month timetable to hammer out a deal was possible.

Mrs May did not directly address the 10 year timetable - which has been played down by No 10 - as she arrived at the summit in Brussels.

EU leaders, including Britain, will discuss the migration crisis at the summit's working sessions today. Britain will then be excluded from a discussion about Brexit over dinner tonight.

As she arrived, Mrs May said: 'I welcome the fact the other leaders will be meeting to discuss Brexit tonight.

Theresa May did find some friendly faces to talk to eventually, including German Chancellor Angela Merkel, left, and European Parliament President Martin Schulz

Theresa May chatted to Irish Taoiseach Enda Kenny ahead of the EU summit in Brussels today

European Council president Donald Tusk greets Theresa May at the start of today's EU summit

'As we are going to invoke Article 50 and trigger Brexit by the end of March next year, it is right the other leaders prepare for those negotiations as we have been preparing.

'We will be leaving the EU, we want that to be a smooth and orderly process as possible - it's not just in our interests, it's in the interests of Europe as well.'

Sir Ivan Rogers warned ministers in October that other EU members believe a trade deal may not be hammered out until the early to mid-2020s, according to the BBC.

Sir Ivan Rogers, the UK's ambassador to the EU, privately warned ministers in October striking a Brexit trade deal could take 10 years

Even when complete, it will then have to go through a marathon and hazardous process of ratification in all the other EU states.

He also reportedly said European leaders believe the deal is likely to be a free trade arrangement rather than continued single market membership.

A No 10 spokesman said the Government was not familiar with the remarks attributed to Sir Ivan and remained positive it could broker a Brexit deal.

He said: 'We don't recognise this.

'The Government is fully confident of negotiating a deal to exit the EU that works in the interest of both the UK and the rest of Europe.'

At a briefing in Westminster, Mrs May's official spokesman said the remarks were not Sir Ivan's 'personal view' but those express to him in Europe.

The spokesman said the Government still believed it was possible to do a deal on leaving the EU that allowed the 'maximum possible access' to the single market within the two year Article 50 negotiating window.

A senior source said: 'It is wrong to suggest this was advice from our ambassador to the EU.

'Like all ambassadors, part of his role is to report the views of others.'

Theresa May, pictured at the Military Awards last night, is in Brussels today for a regular EU summit amid warnings Brexit could take 10 years

Vote Leave campaigner Dominic Raab dismissed the warning from Sir Ivan today, insisting it was the 'worst time' for the EU to erect trade barriers that would damage its own interests.

Mr Raab told the Today programme: 'He was the diplomat who persuaded David Cameron to dilute his ambitions for the renegotiation, which was one reason the referendum was lost. So, he has been rather scarred, in fairness, by his own pessimistic advice in the past.

'But, I think it's reasonable to set out the very worst case scenario for a five to 10-year period to iron out all the details of a trade deal.

'I respect the Foreign Office's professionalism, but they have always been very pro-EU, and very anti-leaving the EU.

'Let's not be consumed by Sir Ivan's gloomy pessimism, let's get behind the Government, let's set out the case for a strong, post-Brexit relationship with the EU on trade, security, and other areas.'

But Labour grandee Peter Mandelson warned a long time scale was 'realistic'.

In evidence to a Commons committee, Lord Mandelson said: 'It will not be achieved simply or quickly.

'While we can’t be certain about how long it will take, a time-span of between five and 10 years seems to me realistic.'

Former cabinet secretary Gus O'Donnell has told the BBC Westminster Hour the deal will take 'at least five years... maybe longer.'

Commission President Jean-Claude Juncker (left) and Council President Donald Tusk (right) are the senior officials in Brussels charged with orchestrating a deal with Brussels

Later tonight, the remaining 27 EU leaders will discuss Brexit during a dinner to which Britain has not been invited.

British sources welcomed the talks among other leaders, saying they showed that the EU recognised that the UK would be leaving the bloc as promised by Mrs May.

The discussion will decide how the EU will organise itself for the talks which will follow Mrs May triggering Article 50, the formal legal mechanism which officially begins the two-year countdown to Brexit.

NICK CLEGG WARNS SECURITY WILL BE HURT BY QUITTING EU COURT Theresa May's determination to take the UK out of the jurisdiction of the European Court of Justice is likely to be 'a serious stumbling block' to the country's post-Brexit safety, Nick Clegg has claimed. In a new report, the Liberal Democrat Brexit spokesman warned the UK could be cut off from access to crime databases and victims of crime could face long waits for justice if Britain fails to maintain the police and security elements of EU membership. The UK could tumble out of EU co-operation measures on crime and security in 2019 unless it secures an 'unprecedented' deal in Article 50 negotiations, warned Mr Clegg. Speaking to the Conservative conference in October, the Prime Minister vowed: 'We will be free to pass our own laws.' Advertisement

A Number 10 source said: 'It shows that they are facing up to the reality that the UK is leaving the EU, that we are going to be triggering Article 50 by the end of March.

'That means they are going to need to know how they are going to handle the process where they have got to work out the position of 27.'

The 27 national leaders are expected to agree the plan over a working dinner in the Belgian capital.

But there could be complications as MEPs claimed the leaders' plan - revealed in a leaked draft - sidelined the European Parliament's Brexit negotiator Guy Verhofstadt.

The former Belgian prime minister said: 'If the government leaders do not take the European Parliament's role seriously, we'll negotiate directly with the British.

'If that's what they want, they'll get it.'

Giving officials from president Jean-Claude Juncker's European Commission the central role could also weaken the ability of Mrs May and her ministers to use their influence directly with counterparts in other governments to secure a favourable Brexit deal.

Mrs May will hold talks with the outgoing president of the European Parliament Martin Schulz in the margins of the Brussels summit.

She will also meet Latvian prime minister Maris Kucinskis and Lithuanian president Dalia Grybauskaite, meaning that she will have held talks with leaders from all EU countries apart from Austria and Bulgaria by the time the summit starts.

In one of the clearest signals yet on the direction of the talks, Brexit Secretary David Davis (pictured during his evidence to Parliament yesterday) said it was vital to respect the referendum demand for lower migration

Yesterday, in one of the clearest signals yet on the direction of the talks, the Brexit Secretary said it was vital to respect the referendum demand for lower migration.

Mr Davis said he believed that the UK's Brexit deal should be 'negotiable' within the 18-month timetable set out by Michel Barnier, the chief Brexit negotiator for the EU.

DOES BREXIT REALLY MEAN BREXIT? CHECK THE DICTIONARY Theresa May famously declared that 'Brexit means Brexit', but now the Oxford English Dictionary (OED) has come up with its own definition. Six months after the Prime Minister first delivered the elusive explanation, lexicographers have clarified that 'Brexit' is 'the (proposed) withdrawal of the United Kingdom from the European Union, and the political process associated with it'. The definition continues: 'Sometimes used specifically with reference to the referendum held in the UK on 23rd June 2016, in which a majority of voters favoured withdrawal from the EU.' Lexicographers said the word filled an empty space in the language, but is now used globally to describe the phenomenon - appearing in many foreign language newspapers. Advertisement

He played down suggestions that the EU will take a punitive approach to negotiations.

In his first evidence session with the Brexit committee, Mr Davis said it was not his job to set immigration policy only to regain complete control over it.

Asked if border control would be up for negotiation, Mr Davis said: 'No.'

The move suggests the Government will completely leave the EU's free movement of workers system - implying a full exit from the single market.

Mr Davis also told the MPs - led by senior Labour MP Hilary Benn - the Government would not publish its Brexit plan before February.

And the Brexit Secretary admitted he was yet to meet with any ministers in Germany, Europe's biggest economy.

Grilled on migration, Mr Davis told the committee: 'The example I will point you to is the Swiss example.

'They thought they had control over their own migration via an emergency brake system.

'When they tried to exercise it they were unable to because it was tied into so many other treaties.

'What we have to bear in mind is we have to pay respect to the outcome of the referendum, there has got to be clear control by this Parliament.'