Prime Minister Rishi Sunak has outlined details of the "new Windsor Framework" agreed with the European Union to overcome trade barriers in Northern Ireland following Brexit.
The prime minister said the agreement was a "historic" and a "decisive breakthrough" that "delivers smooth-flowing trade within the whole of the United Kingdom, protects Northern Ireland's place in our union and safeguards sovereignty for the people of Northern Ireland".
The new deal includes:
* Green and red lane trade routes - where goods staying in the UK will use a green lane to avoid customs bureaucracy, while goods moving to the EU will use a red lane
* UK VAT and excise changes will apply in Northern Ireland - British products such as food and drink, trees, plants and seed potatoes will be available in Northern Ireland and pet travel requirements have been removed
* A "landmark" settlement on medicines so drugs approved for use by the UK's medicines regulator will be automatically available in every pharmacy and hospital in Northern Ireland
* A new "Stormont brake" - to safeguard sovereignty in Northern Ireland. Stormont can stop changes in EU goods laws from applying in Northern Ireland. If the brake is pulled, the UK government will have a veto that will apply permanently
For weeks, there has been speculation over whether a new deal could be thrashed out three years after Brexit took place as Mr Sunak entered talks with the EU.
But terms of the deal were revealed at a news conference following final talks between Mr Sunak and European Commission President Ursula von der Leyen in Windsor this lunchtime.
Mr Sunak said the agreement "marks a turning point for the people of Northern Ireland" that "fixes the practical problems they face" yet "preserves the balance of the Belfast Good Friday Agreement".
On the changes to customs and VAT rules, Mr Sunak said: "This means we have removed any sense of a border in the Irish Sea."
Ms von der Leyen said the 27-page, 13,031-word framework "will allow us to begin a new chapter" and it "provides for long-lasting solutions that both of us are confident will work for all people and businesses in Northern Ireland".
The two leaders were glowing in their respect for each other, with Ms von der Leyen calling the PM "dear Rishi" a few times and said they were "honest with each other about the difficulties in our bilateral relationship and it was vital to put that on the right footing".
Mr Sunak said: "The United Kingdom and European Union may have had our differences in the past, but we are allies, trading partners and friends.
"Something that we've seen clearly the past year as we joined with others to support Ukraine. This is the beginning of a new chapter in our relationship."
Mr Sunak put the deal - the biggest move of his premiership - to his cabinet on Monday afternoon during a virtual meeting but a vote by MPs in the Commons is not expected until possibly next week.
Following speculation there may not be a vote on the deal by MPs, Mr Sunak confirmed parliament will have a vote "at the appropriate time".
On whether Tory Brexiteers and Northern Ireland's Democratic Unionist Party (DUP) - who has refused to form an executive in Stormont in protest of the former protocol - may try to block the deal, Mr Sunak said it is "not about politicians" and is about "what's best" for the people of Northern Ireland.
Earlier in the day, Brexiteer Jacob Rees-Mogg warned Mr Sunak of a possible Tory revolt if the DUP did not support the deal.
DUP leader Sir Jeffrey Donaldson said in a statement that the agreement showed "significant progress has been secured across a number of areas", but there remained "key issues of concern", adding: "There can be no disguising the fact that in some sectors of our economy EU law remains applicable in Northern Ireland."
He said his party would "study the detail" of the framework and "where necessary we stand ready to engage with the government in order to seek further clarification, re-working or change as required".
However, Sinn Fein's Michelle O'Neill said there should now be no more delays to the restoration of the Stormont institutions.
"I was always very clear that the protections that were secured within the protocol were very necessary, they remain necessary," she told Sky News.
"Protecting those things that were working and smoothing out the things that needed to be fixed, that is the position we are standing in this evening.
"All different parties need to sit down at the executive table taking the decisions which impact on people's lives, that is where we should be."
Ireland's prime minister Leo Varadkar backed the deal, saying it provided "workable and durable" solutions.
He added: "The agreement also paves the way for new and more positive relations between the UK and the EU and between the UK and Ireland.
"This is a time of great trouble in the world. We need to be partners and friends. There is so much more that unites us than divides us."
Labour leader Sir Keir Starmer also supported the deal, saying: "We will not snipe. We will not seek to play political games. And when the prime minister puts this deal forward for a vote, Labour will vote for it.
"The protocol will never be perfect. It is a compromise. But I have always been clear that, if implemented correctly, it is an arrangement that can work in the spirit of the Good Friday Agreement.
"And that now it's been agreed, we all have an obligation to make it work."
Mr Sunak will meet the 1922 Committee of backbench Tory MPs on Tuesday evening to try to persuade them to back the deal.
But first he made a statement on the deal to MPs in the House of Commons.
There has been early support from Brexiteer and Northern Ireland minister Steve Baker, who told Sky News the framework "restores Northern Ireland's place in the union".
He added: "I think this is a win and I think it's very important in politics to know when you've had a win-win solution for all sides - bank it and move forwards... this is a time to bank what is a radical improvement for the people of Northern Ireland."
And a statement from this afternoon's cabinet meeting readout showed further Brexit faithfuls giving their backing, with the deputy PM Dominic Raab saying the framework was "a remarkable accomplishment which would be a success story for the region" and home secretary Suella Braverman praising the Stormont brake.
The deal follows frustrations around the Northern Ireland Protocol, which aimed to prevent creating a hard border on the island of Ireland - but effectively placed a border in the Irish Sea.
This was something former prime minister Boris Johnson promised would not happen when he signed off on the original deal with the EU.
The DUP has refused to form an executive at Stormont until the protocol is ditched, meaning the Assembly has not been functioning for months.
Some businesses have ceased trading due to the extra cost and bureaucracy created by goods coming into Northern Ireland from the rest of the UK having to be checked over concerns they could end up going into the EU over the border in Ireland.
Mr Johnson introduced the Northern Ireland Protocol Bill to override that part of the Brexit deal but this caused tension with the EU, who said the move risked breaching an international treaty.
The ex-prime minister told Sky News last week that continuing with the bill was the "best way forward".
But the bill's passage through parliament was paused by Mr Sunak and will now be dropped, in return for the EU dropping legal proceedings against the UK.
Ms Von der Leyen headed off to meet King Charles for tea at Windsor Castle after she and the PM announced the deal.