Amnesty International today called for Guantánamo Bay to be shut by the end of the year.
The human rights organisation's secretary general, Irene Khan, said she hoped the next US president would announce its closure on December 10 - the 60th anniversary of the Universal Declaration of Human Rights.
"It would be a great occasion for the new US president to announce the closure of Guantánamo on that day," she said.
As the charity published its annual report, Khan said all three presidential candidates had pledged to shut down Guantánamo Bay.
She also accused western governments of failing to do enough to tackle human rights abuses.
The organisation's annual checklist of human rights outrages showed people were still tortured or ill-treated in at least 81 countries.
Men and women also faced unfair trials in at least 54 countries and were denied free speech in at least 77, the report said.
"The reason why the Amnesty International report highlights the role of the United States is because the US is the world's superpower and as such its performance sets the standard for other governments around the world," Khan said.
"That's why we have high expectations that the new US president will set a new direction that the US will engage positively with human rights and will begin first by setting its own house in order."
Amnesty challenged world leaders to "apologise for six decades of human rights failure" and to make a new commitment to work for improvements.
The report renewed criticism of the UK for its policy of deportations to unstable countries, secret terror hearings and failing to fully investigate alleged state collusion in killings in Northern Ireland during the Troubles.
"We would like the British government to correct its own approaches on control orders on pre-charge detention - which could all send a clear message - but also we would like the British government to play a very active role, as it has indeed done in Burma and other places, but make sure that human rights are in the centre of many of those political processes," Khan said.
Speaking on Sky News, she called on Britain to "clean up its act" and said world leaders "cannot be seen to be leaders unless they do so by example".
The EU should investigate the "complicity of its member states" in renditions of terrorist suspects, she added.
"But there is an opportunity in the coming year for world leaders to set a new direction. There are new leaders coming to power, in the US for instance, there are new countries emerging on the world stage, and the United Kingdom could certainly lead together with them."
The organisation also called on China to adhere to its human rights pledges and on Russia to show greater tolerance for political dissent.
© 2008 The Guardian