It's all about giving Ukraine a strong position, according to EU Commission President Ursula von der Leyen.
Ukraine must get the resources to arm and protect itself, from economic survival to military endurance. We must transform Ukraine into a porcupine, unpalatable to anyone who intrudes, she says.
We need comprehensive security guarantees for Ukraine.
The summit was convened by British Prime Minister Keir Starmer. He says at a press conference afterwards that it's now about strengthening "our contacts with the USA".
Europe must do the heavy lifting, but we must have the USA's support, he says.
"Time for action"
Starmer reports that the leaders have agreed to continue the military aid to Ukraine and simultaneously increase the economic pressure on Russia.
Plans are underway for a coalition of countries, led by the UK, to drive and guarantee a fair peace for Ukraine.
We will develop a coalition of those willing to defend an agreement for Ukraine and guarantee peace, says Starmer.
Keir Starmer calls it a historic turning point.
This is not a time for more talk. Now is the time for action.
Build-up and guarantees
Ursula von der Leyen emphasizes that we must "immediately build up Europe". The EU Commission will propose a plan for this at the EU meeting on March 6.
We must really increase our strength significantly.
NATO Chief Mark Rutte also stresses that Europe must ensure Ukraine has what it needs and provide security guarantees.
The goal is to ensure that Russian President Vladimir Putin "never, ever again tries to attack Ukraine".
"Decisive for security"
As the meeting began at Lancaster House in London, a stone's throw from Buckingham Palace, Starmer spoke about it as a moment for the entire European security that occurs "only once in every generation".
A good result for Ukraine is not just about right or wrong. It is decisive for the security of every country and many others, said Starmer.
Also attending the meeting were Ukraine's President Volodymyr Zelensky and 16 other leaders from Europe – including Prime Minister Ulf Kristersson – as well as Canada's Prime Minister Justin Trudeau.
The summit takes place against the backdrop of Zelensky's dramatic meeting with US President Donald Trump on Friday, which ended in a heated argument.
The following leaders are participating in Sunday's summit in London
* UK Prime Minister Keir Starmer
* Ukraine's President Volodymyr Zelensky
* France's President Emmanuel Macron
* Germany's Chancellor Olaf Scholz
* Poland's Prime Minister Donald Tusk
* Italy's Prime Minister Giorgia Meloni
* Spain's Prime Minister Pedro Sanchez
* Czech Republic's Prime Minister Petr Fiala
* Netherlands' Prime Minister Dick Schoof
* Finland's President Alexander Stubb
* Denmark's Prime Minister Mette Frederiksen
* Norway's Prime Minister Jonas Gahr Støre
* Sweden's Prime Minister Ulf Kristersson
* Turkey's Foreign Minister Hakan Fidan
* Romania's Acting President Ilie Bolojan
* Canada's Prime Minister Justin Trudeau
* EU Commission President Ursula von der Leyen
* EU Council President António Costa
* NATO Secretary-General Mark Rutte
UK Prime Minister Keir Starmer highlighted four crucial points in the continued efforts to achieve peace in Ukraine:
Continued military support to Ukraine as long as the war continues, and further pressure on the Russian economy.
A peace must include Ukraine's sovereignty and security, and Ukraine must be part of any peace negotiations.
In the event of a peace, the European leaders agree on the goal of preventing any future attempts by Russia to reinvade Ukraine.
A "coalition of the willing" countries will be created to guarantee peace in Ukraine.
