Human rights groups have vowed to track George W Bush round the world after their success in forcing him to cancel a trip to Switzerland amid concerns over protests and a threatened arrest warrant.
Katherine Gallagher, a lawyer with the New York-based Centre for Constitutional Rights, said: "The reach of the convention against torture is wide. This case is prepared and will be waiting for him wherever he travels next. "Torturers, even if they are former presidents of the United States, must be held to account and prosecuted."
Although Bush has travelled freely round the world since leaving the White House in January 2009, human rights groups believe he is vulnerable to prosecution after admitting in his autobiography last November that he authorised waterboarding and other interrogation techniques.
"Waterboarding is torture, and Bush has admitted, without any sign of remorse, that he approved its use," said Gallagher, who is also vice-president of the International Federation for Human Rights.
Bush's staff, as well as US embassies around the world, will have to factor into their planning of future trips whether a country is a signatory to the convention on torture, as most countries are, which should at least theoretically trigger near-automatic action by legal authorities, and negotiate with governments to ensure there will be no arrest warrants. They will also seek assurances that Bush has diplomatic immunity.
Since the arrest of the late Chilean dictator Augusto Pinochet in London in 1998 over alleged murders, senior politicians linked to war, internal conflict and oppression have had to be more careful in their travel plans.