Allied leaders have gathered in Wales for the 2014 Nato summit, with strategies for dealing with Russia and the Islamic State high on the agenda.
World leaders including Barack Obama, David Cameron and Ukrainian President Petro Poroshenko have all convened at the Celtic Manor Resort in Newport, with Afghanistan and Ukraine being the first day's official topics.
Nato Secretary General, Anders Fogh Ramussen, was clear on the goals of the summit:
"Our NATO summit here in Wales will be one of the most important summits in the history of our alliance. A crucial summit at a crucial time. We are faced with a dramatically changed security environment; to the east, Russia is attacking Ukraine; to the south-east, we see the rise of a terrorist organisation the so-called Islamic State that has committed horrific atrocities; to the south, we see violence, insecurity, instability," he said.
Barack Obama and David Cameron have both pledged to use the summit to form a military coalition against Isis, following the killings of US journalist James Foley and Steven Sotloff in the self-proclaimed caliphate.
The Nato Summit in Wales, the largest gathering of international leaders ever to take place in Britain, will continue until 5 September.