David Cameron has hailed the anti-corruption summit he is hosting in London as "the biggest demonstration of the political will to address corruption that we have seen for many, many years".
The summit has brought together more than 40 countries including 12 heads of state and government.
Speaking at the end of the first day, he said attendees had shown "far more political will not just for words, but for action that will make a difference".
David Cameron's comments about corruption in Afghanistan are "unfair", a spokesman for the Afghan embassy has said.
The spokesman said: "President Ghani and his Government since in office have taken major steps to fight corruption.
"Countering corruption is a top priority along security issues for the National Unity Government.
"We have made important progresses in fighting systematic capture in major national procurement contracts and are making progress on addressing institutional issues as well as issues related to impunity.
"Therefore calling Afghanistan in that way and taking bold decisions by NUG is unfair."
David Cameron hoped to sign up a global declaration against corruption - but only six countries put pen to paper.
Why is it happening? Who is going? And will it get awkward after the Prime Minister's 'corruption gaffe'?
David Cameron has praised Nigeria and Afghanistan for the action they have taken in combating corruption.