G20 summit in Seoul

A South Korean mililtary guard wearing traditional costume prepares for the arrival ceremonies for the G20 leaders Photograph: Romeo Gacad/AFP/Getty Images

South Korean military guards carry Japanese flags as they await the arrival of the Japanese prime minister, Naoto Kan (not pictured) Photograph: Romeo Gacad/AFP/Getty Images

Anti-G20 protesters gather near Seoul station as world leaders arrive in the city Photograph: Ted Aljibe/AFP/Getty Images

A view of a 'Green Growth' session of the G20 business summit Photograph: Hoang Dinh Nam/AFP/Getty Images

A South Korean protester is surrounded by police officers as he stages a one-man demonstration against the South Korean government's development project on four major rivers Photograph: Jung Yeon-je/AFP/Getty Images

David Cameron delivers a speech during the G20 business summit Photograph: Yonhap/AFP/Getty Images

Cameron during a bilateral meeting with the Russian president, Dmitry Medvedev Photograph: Andy Rain/EPA

Obama signs the guestbook before talks with South Korea's president, Lee Myung-Bak, at the presidential Blue House in Seoul Photograph: Tim Sloan/AFP/Getty Images

The US Treasury secretary, Timothy Geithner (left), talks to the South Korean finance minister, Yoon Jeung-hyun Photograph: AP

The US president, Barack Obama, meets the Chinese president, Hu Jintao Photograph: Tim Sloan/AFP/Getty Images

Obama holds talks with the German chancellor, Angela Merkel, at the Grand Hyatt hotel Photograph: Tim Sloan/AFP/Getty Images

Demonstrators clash with riot police as they try to march through Seoul Photograph: Jo Yong-hak/Reuters

Protesters march during an anti-G20 demonstration Photograph: AP

Heavy rain falls as South Korean policemen block the traffic during an anti-G20 protest Photograph: Damir Sagolj/Reuters

A commuter looks out of a bus window as South Korean police line the streets during an anti-G20 demonstration Photograph: Daniel Berehulak/Getty Images

A 'Stop G20' sign lies in the street after a protest Photograph: Damir Sagolj/Reuters

Anti-globalisation protesters burn a mock coffin Photograph: Jung Yeon-je/AFP/Getty Images

A South Korean security official stands guard outside the G20 summit venue as a police officer passes on an electric scooter Photograph: Stephen Morrison/EPA

David Cameron (2nd left) goes jogging with his Spanish counterpart José Luis Rodríguez Zapatero (2nd right) in Seoul Photograph: Reuters

David Cameron addresses a press conference on the sidelines of the G20 summit Photograph: Ed Jones/AFP/Getty Images

David Cameron drinks tea with monks at the Bongeunsa temple in Seoul Photograph: Darren Staples/PA

Russia's president, Dmitry Medvedev (2nd right), meets Turkey's prime minister, Tayyip Erdogan (right) and his Italian counterpart, Silvio Berlusconi (left) on the sidelines of the G20 summit Photograph: Ria Novosti/Reuters

A model wears traditional South Korean costume at a fashion show for the G20 first ladies at Seoul's Changdeok palace Photograph: AP

Police patrol the security perimeter of the G20 summit venue Photograph: Ed Jones/AFP/Getty Images

First ladies of the G20 nations watch a fashion show featuring traditional South Korean costume at Changdeok palace Photograph: AP

David Cameron and Barack Obama listen to the South Korean president, Lee Myung-bak, speak during a working dinner at the G20 summit Photograph: EPA

South Korean police remove a union protester during a demonstration near the Ritz-Carton hotel in Seoul Photograph: Kim Jae-hwan/AFP/Getty Images

The US president, Barack Obama, addresses a press conference at the close of the G20 summit Photograph: Stephen Morrison/EPA

Delegates walk past a tower of screens displaying the flags of the G20 member countries at the Seoul international convention centre Photograph: Romeo Gacad/AFP/Getty Images