Image source, Reuters

The big EU figure at tonight's meeting is the European Commission President Ursula von der Leyen.

But how did she become one of the key players in the post-Brexit trade story?

Brussels born and bred, von der Leyen is a former German defence minister, a long-term ally of Chancellor Angela Merkel, and the first woman to head the EU's powerful executive.

She studied economics at London's LSE and medicine in Hanover before going into politics.

When she replaced Jean-Claude Juncker in the EU's top job on 1 December 2019, she said: "For me, it's like coming home."

Read more about Von der Leyen, her background and her views here.

So you have just seen our piece on the UK Internal Market Bill - a touch complicated isn't it?

Watch this video below and it will explain why the devolved nations are less than happy with the law's implications...

Image source, AFP

In the background of the Brexit talks, the UK government is trying to get some key bits of Brexit legislation through parliament.

And earlier this evening, it suffered fresh defeats in the House of Lords over its blueprint for protecting trade between different UK nations after Brexit.

Opponents of the Internal Market Bill argue it will centralise power in London after the UK regains certain powers from the EU.

UK ministers say the bill is needed to help firms trade across the country.

Read more about the row - and the bill - here.

We know that time is running out until end of transition period on 31 December.

So, right now, in that building behind me, we have Prime Minister Boris Johnson talking to European Commission president Ursula von der Leyen.

The stakes are extremely high - but we are still not sure if this is going to be a decisive meeting.

In traditional trade negotiations, you would think this is the moment. This is where these two leaders say come on, we have been staring into the whites of each others eyes for long enough now, time for us both to make those difficult political compromises.

But it is just not that simple because there is this clash of ideologies in that building and one that we have had since the start of Brexit.

The UK government does not want to relinquish national sovereignty and sign up to a new rule book, whereas from an EU perspective, their priority is to protect their single market from what they see as damaging and unfair competition from Britain.

And that may be where we are stuck.

They both say they want a deal, but no deal is definitely a potential on tonight's menu, or we may end up with neither breakthrough or breakdown - just enough for the two sides negotiators to keep on talking.

We will let you know as soon as we do.

Image source, Getty Images

Apologies for the earlier fish puns - it really is a serious issue in these talks, and an emotional one, making it no surprise that it is one of the final outstanding issues in the post-Brexit trade talks.

Supporters of Brexit see it as a symbol of UK sovereignty that will now be regained.

The UK says any new agreement on fisheries must be based on the understanding that "British fishing grounds are first and foremost for British boats".

But the EU wants access for its boats and says reaching a "fair deal" on fisheries is a pre-condition for a free trade agreement (with no tariffs or taxes on goods crossing borders).

So, while fishing is a tiny part of the economy on both sides of the Channel, it carries big political weight.

Read more about the importance of the issue here.

Image source, Getty Images

Fish is on the menu in more ways than one tonight...

Yes, Boris Johnson and Ursula Von der Leyen are chewing over that issue as one of their major sticking points in a post-Brexit trade deal.

And you can't deny their plates are full.

But, it is the moment we have all been waiting for - or at least all of the political nerds among us - tonight's menu has been published!

For starters, the pair were treated to a pumpkin soup and those all important scallops.

Main is steamed turbot and mashed potatoes, with wasabi and vegetables.

And dessert is Pavlova with exotic fruit and coconut sorbet.

It may be a small detail, but it is one we enjoyed. We hope you (and they) did too.

Image source, Getty Images

• Brexit happened but rules didn't change at once: The UK left the European Union on 31 January but leaders needed time to negotiate a deal for life afterwards - they got 11 months
• Talks are on again: The UK and the EU have until 31 December to agree a trade deal as well as other things, such as fishing rights
• If there is no deal: Border checks and taxes will be introduced for goods travelling between the UK and the EU. But deal or no deal, we will still see changes

So what happens next? Here's our guide - all you need to know about the UK leaving the EU

Jessica Parker
BBC political correspondent

Image source, Getty Images

So, the meeting is under way.

Two people, alongside a small group of aides, are working out what kind of trading relationship the EU and the UK might have for years to come.

And they’re in that room because, despite stalled negotiations, both sides still seem to want this deal enough to keep trying.

We are waiting for the white smoke, but we don't know when it will come.

And a full on breakthrough, where Boris Johnson and Ursula von der Leyen suddenly emerge triumphant? Well, that certainly isn’t expected.

Perhaps we may get a mutual nod that they shouldn’t give up just yet.

But nothing is certain and both sides know that to keep trying, in itself, isn’t enough - partly because there’s so little time left, but also because tangible compromises are needed in order to progress things any further.

Reality Check

Image source, Getty Images

Many aspects of the UK and EU's future relationship remain uncertain.

But the one thing we do already know is some things will change from 1 January 2021.

So what are some of the most important things for people to think about?

And other issues that still remain unresolved?

Read more from our BBC Reality Check team here.

Simon Jack
BBC Business Editor

Michael Gove was in confident mood in the Commons earlier as he announced a series of measures to address urgent concerns about the operation of trade between Northern Ireland and the rest of the UK.

With a couple of rare exceptions, all goods going from UK to NI will be exempt from EU tariffs – a prospect that was a real concern as Norther Ireland will essentially remain in the single market.

This applies even if there is no deal – in fact, if there is a deal the issue of tariffs falls away anyway.

Proposed food safety checks on goods entering Northern Ireland from GB will be waived for a grace period of three months.

That will come as a great relief to suppliers and retailers but the Food and Drink Federation told the BBC that while it bought valuable time, it was a problem postponed not solved.

Chairman of Tesco John Allen said that three months was better than nothing and told the BBC he welcomed the announcement as “a step in the right direction”.

Supermarkets will be given extra time to phase in new checks, ensuring food supplies from GB to Northern Ireland do not face disruption from 1 January - whether or not there is a Brexit deal.

This will allow supermarkets to adapt their systems to deal with new Brexit controls required by the EU.

It is part of the agreement reached between the UK and EU on how the new Irish Sea border will operate.

Outlining details of the agreement in parliament on Wednesday, Cabinet Office Minister Michael Gove said the government had heard "loud and clear" the concerns of supermarket firms that more flexibility was needed.

The rules will apply whether or not the two sides can agree a trade deal.

Read more here

If you are just joining us, welcome to tonight's BBC Politics live page following the latest chapter in the post-Brexit trade deal saga.

Prime Minister Boris Johnson is in Brussels holding talks over dinner with European Commission President Ursula von der Leyen.

The pair are trying to thrash out the major sticking points remaining in securing a trade deal between the UK and EU.

But we are waiting for the conclusion.

For the full story, click here - but remember to come back to us for more live updates.

A little earlier, before tonight's meeting began, BBC Brussels correspondent Nick Beake spotted a first in the city since the UK left the EU...

Image source, Reuters

Tonight's meeting comes hours ahead of an EU Council meeting in Brussels.

That means on Thursday, all of the leaders of the members states - such as Germany's Anglea Merkel and France's Emmanuel Macron - will be sat round a table to discuss the issues of the day - on coronavirus, climate change and security.

But perhaps surprisingly, Brexit won't be one of them.

In a invitation letter, external from European Council President Charles Michel, he said "negotiations are on-going based on our common mandate" - basically, they all agree on their position - and as a result, "it is not the intention to plan a discussion on the matter".

Michel did reveal though that Ursula von der Leyen "will debrief us on the state of play" after her talks with Boris Johnson.

We bet they are as eager to hear the outcome as we are...

Behind those closed doors in Brussels, the UK prime minister and European Commission president are trying to thrash out those "significant differences" we have heard so much about.

But what if Boris Johnson and Ursula von der Leyen fail to agree a trade deal by 31 December?

Well, the two sides would start to trade on World Trade Organisation rules, and in this scenario, the UK and EU would impose tariffs – or taxes on imported goods.

The average EU tariff is pretty low (about 2.8% for non-agricultural products), but in some sectors, tariffs can be quite high.

Cars could be taxed at 10%, for example, and some agricultural tariffs could be even higher – such as 35% for dairy products.

Click here to read what else could change.

Laura Kuenssberg
Political editor

Boris Johnson travels to Brussels for the first time in months to sit and break bread with the EU Commission chief Ursula von der Leyen.

It is more than a standard diplomatic dinner.

It is possible that the encounter could be the moment at which the UK and the EU conclude that there cannot be a trade deal now, and that after decades of political and economic ties, efforts to say a polite political farewell have failed, with all the consequences that might entail.

The purpose of the dinner however is not to call a halt.

But nor is the purpose to proclaim that a deal's been done.

The reason for the meeting is to see if both sides are willing in principle to tolerate the notion of budging, after the negotiations, and frankly negotiators, have been exhausted.

Read Laura's latest blog in full here

And the meeting has begun.

Boris Johnson and Ursula von der Leyen posed for pictures before heading in.

And they had a few short words about mask wearing too...

After taking them off for the photo opportunity, the European Council president instructed the PM to put his covering back on.

"You run a tight ship here," said Johnson. "And quite right too!"

And he's off!

Boris Johnson has left the British Embassy in Brussels and is on his way to the European Commission.

There awaits Ursula von der Leyen for their meeting.

Image source, Jessica Taylor/ UK Parliament

At Prime Minister’s Questions in the House of Commons this afternoon Mr Johnson told MPs "a good deal is still there to be done", but, he said the EU are making demands that he cannot accept, such as the UK doesn’t have a control over fishing in its own waters.

Ireland's deputy leader said Boris Johnson he believed would be willing to make concessions to ensure there is a deal with the EU.

Leo Varadkar – who was Taoiseach during last year’s Brexit negotiations – told RTE the EU had "more to gain and more to salvage" than they had to lose over an agreement.

But Varadkar said both sides will need to "move a little bit" to ensure a deal is reached.