Article 50 is the name of the agreement explaining how a country can leave the EU. Created as part of the Treaty of Lisbon, it was signed by all members of the EU in 2009.
The document states that a country has two years to agree the terms of it's departure from the EU, and that time can only be extended with agreement of all other members.
The terms of the departure must be approved by the majority of member states, which is 72% of markets.
What happens next?
Articles you may be interested in:
It's official, Article 50 has been triggered, and the formal process of the UK leaving the EU has begun. Below is the official letter received by President of the European Council, Donald Tusk, today:
You may also be interested in:
Wednesday 29th Match: Susanna is wearing a white/floral dress by Marks & Spencer, yellow suede shoes by La Redoute and pandora hoop earrings.
I’m not a person who can sit around doing nothing and I’m sure that neither of you are. Also they say if you retire you don’t live that much longer
Today we were joined by Hollywood star and Queen of showbiz, Dame Joan Collins. Dame Joan talked about whether she will retire, being a ‘Brexiteer’ and her thoughts on the ‘legs-it’ controversy.
On her support of Brexit, Dame Joan told presenters Piers Morgan and Susanna Reid: “I think it’s going to be very good for us.”
On yesterdays ‘legs-it’ controversy, she said: “Was I offended? Well no I actually giggled and then I showed it to [husband] Percy and I said, ‘what do you think of these legs’ and he said, ‘yours are better’”.
Watch the full interviews here.
Former England footballer Rio Ferdinand lost his wife Rebecca after a short battle with cancer in 2015. She was aged just 34.
Rio opened up to Piers and Susanna about the pain of losing his wife, and how he has helped his three children deal with the tragedy.
Rio urged men to show their feelings and to talk. He also expressed his sympathy for John Frade who was widowed in last week's attack on Westminster.
Watch the full interview above.
Richard Arnold spoke exclusively to one of the biggest music stars on the planet, Ed Sheeran. Richard caught Ed just before he prepared to WOW the crowds at his Teenage Cancer Trust gig at the Royal Albert Hall.
They discussed Ed wanting a family, going clubbing, how he stays down to earth and much more.
Watch the full interview above.
The death of a loved one can be devastating, and affects everybody in different ways. If you, or someone you know, has been affected by bereavement you can get help and support from the following organisations:
Cruse Bereavement Care offer support, advice and information to children, young people and adults when someone dies. Support is offered face to face, by telephone or over e-mail.
Phone: 0808 808 1677 (England, Wales and Northern Ireland)
0845 600 2227 (Scotland)
Hope again offer support for children and young people affected by the death of someone close.
Phone: 0808 808 1677 (Monday - Friday, 9:00am - 5:00pm)
The Bereavement Trust offers comfort, support and practical advice to the bereaved in the evenings. every evening of the year.
Phone: 0800 435 455 (Every evening, 6pm - 10pm)
Winston's Wish provides services to bereaved children, young people and their families and offer practical support and guidance to anyone concerned about a grieving child.
Phone: 08088 020 021
1. Prime Minister Theresa May has said "now is the time to come together" as she prepares to trigger the start of the UK's formal withdrawal from the EU. The Prime Minister will chair a meeting of the Cabinet as the letter formally invoking the Article 50 withdrawal process is dispatched to Brussels.
The inquests for the victims will open at Westminster's Coroner Court today and Masood's inquest will open at the same court on Thursday. Twelve people are still being treated at hospitals across London. Two men remain in police custody as the investigation by the Met's Counter Terrorism Command into last Wednesday's terrorist attack in Westminster continues.
Schools in England are facing their toughest spending squeeze in two decades, jeopardising standards in the classroom, MPs have warned. The Commons Public Accounts Committee said class sizes would rise and some subjects would be dropped as schools increasingly relied on unqualified staff in a struggle to make ends meet.
Court hearing for One Direction singer Louis Tomlinson, arrested following a scuffle at Los Angeles International Airport. Tomlinson was put under citizen's arrest and charged with simple battery and a misdemeanour for allegedly tackling a paparazzo to the ground and assaulting a female fan.
Former England player, Rio Ferdinand, opens up about the pain of losing his wife Rebecca after a short 10 week battle with breast cancer. He is now bringing up their three children on his own and describes how his life and the lives of their children have changed.