The PM says he fought “head, heart and soul” but that Britain now needs a new leader to oversee negotiations to leave the EU.
David Cameron has resigned as Prime Minister after UK voters made the historic decision to leave the European Union.
A tearful Mr Cameron – his wife by his side – said the country needed “fresh leadership” and is now understood to be meeting the Queen at Buckingham Palace.
The PM campaigned to remain in the EU but the public rejected his arguments and chose to leave the EU by 51.9% to 48.1%.
Speaking outside Downing Street, the PM said he would aim to have a new leader in place by the Conservative party conference in October.
“The British people have voted to leave the European Union and their will must be respected,” Mr Cameron said.
“The country requires fresh leadership to take it in this direction,” added the PM.
“I will do everything I can as Prime Minister to steady the ship over the coming weeks and months, but I do not think it would be right for me to try to be the captain that steers our country to its next destination.
“This is not a decision I’ve taken lightly but I do believe it’s in the national interest to have a period of stability and then the new leadership required.”
Mr Cameron said he had fought the “only way I know how … head, heart and soul” to stay in the EU but that voters had chosen a different path.
With tears in his eyes, his voice cracking, the PM said: “I love this country, and I feel honoured to have served it and I will do everything I can in the future to help this great country succeed.”
He then turned away, took his wife’s hand and headed back into Number 10.
The PM also used his speech to congratulate Leave campaigners – who included Boris Johnson and his friend Michael Gove – for their “spirited and passionate case”.
Appearing at a Leave press conference, both men paid tribute to the PM and said they are sorry he is stepping down.
Scotland’s First Minister Nicola Sturgeon – who has said a second independence vote is now “highly likely” – also wished the Prime Minister well.
Those potentially in the frame to succeed David Cameron include Education Secretary Nicky Morgan – reportedly mulling whether she should pursue the top job – and Home Secretary Theresa May.
Mr Cameron also tried this morning to ease the economic fallout of Brexit that has seen the FTSE share index shed more than £100bn and triggered a big drop in the value of the pound.
The PM stressed the economy was “fundamentally strong” and said there would be no immediate changes for businesses – as well as for EU citizens in the UK or Britons living in Europe.
“There will be no initial change in the way our people can travel, in the way our goods can move or the way our services can be sold,” Mr Cameron said.
Trade issues will be at the heart of talks to thrash out exactly how Britain’s relationship with the EU will work in future – negotiations that many expect will last for years.