Among the hundreds of thousands of leaked State Department documents were candid and often unflattering assessments of foreign leaders.
The classified diplomatic cables were released Sunday by online whistle-blower WikiLeaks.
The massive release of material intended for diplomatic eyes only is sure to ruffle feathers in foreign capitals, a certainty that prompted U.S. diplomats to scramble in recent days to shore up relations with key allies in advance of the disclosures.
The cables contain many tart comments. French President Nicolas Sarkozy was described as an "emperor with no clothes" and Afghan counterpart Hamid Karzai was said to be "weak" and "easily swayed."
Russian President Dmitry Medvedev, Russia's head of state, was described in one 2008 cable as playing "Robin to (Russian Prime Minister Vladimir) Putin's Batman."
Libyan leader Moammar Gadhafi, meanwhile, was described as erratic and in the near constant company of a Ukrainian nurse who was described in one cable as "a voluptuous blonde," according to The New York Times.
The newspaper said a batch of documents raised questions about Italian Prime Minister Silvio Berlusconi and his relationship with Putin. One cable said Berlusconi "appears increasingly to be the mouthpiece of Putin" in Europe, the Times reported.
German news weekly Der Speigel said U.S. Secretary of State Hillary Rodham Clinton asked her ambassadors in Moscow and Rome to inform her whether there was any truth in rumors that Berlusconi and Putin have private business ties. Both men have denied such claims.
'Partying hard'
Another cable from Rome to Washington described Berlusconi as "physically and politically weak" and asserted that his "frequent late nights and penchant for partying hard mean he does not get sufficient rest." Berlusconi was also seen as "vain and ineffective as a modern European leader."
According to Der Spiegel, one cable sent from the American Embassy in Moscow said that Medvedev's wife Svetlana "remains the subject of avid gossip." It suggested that the Russian first lady had compiled a list of officials who should be made to "suffer" due to their alleged disloyalty to her husband.
Another cable told how Gadhafi "appears to have an intense dislike or fear of staying on upper floors, reportedly prefers not to fly over water, and seems to enjoy horse racing and flamenco dancing."
Gadhafi, who has ruled Libya for over 40 years, is also said to rely heavily on his staff of four Ukrainian nurses, including a woman named Galyna Kolotnytska, who is described as a "voluptuous blonde."
"Some embassy contacts have claimed that Gadhafi and the 38-year-old Kolotnytska have a romantic relationship. While he did not comment on such rumors, a Ukrainian political officer recently confirmed that the Ukrainian nurses 'travel everywhere with the Leader,' " the cable read.
Other cables posted by the New York Times describe U.S. officials' meetings with Karzai's half-brother, who heads a provincial council in southern Afghanistan. Ahmad Wali Karzai is depicted as an operator who doubts the value of elections and "is widely understood to be corrupt and a narcotics trafficker."
A U.S. diplomat described German Chancellor Angela Merkel as someone who "avoids risk and is seldom creative."
The U.K.'s Guardian newspaper said other documents describe how Yemeni President Ali Abdullah Saleh was "dismissive, bored and impatient" during a meeting with White House counter-terrorism chief John Brennan and that a South African government official described Zimbabwean president Robert Mugabe as "the crazy old man."
According to Der Speigel, another cable discussing the wife of Azerbaijan leader Ilham Aliyev said she had extensive plastic surgery and that as a result it is possible to confuse her for one of her daughters.
Britain's Sun newspaper told how one British former government minister was described as a "hound dog where women are concerned." Prince Andrew is also accused of "rude behavior," The Sun added.
The Obama administration has been bracing for the release for the past week. Top officials have notified allies that the contents of the diplomatic cables could prove embarrassing because they contain candid assessments of foreign leaders and their governments, as well as details of American policy.
But in the wake of the disclosures, Francois Baroin, spokesman for the French government, said Monday that "France is very much in solidarity with the American administration."
He described WikiLeaks a "threat against the authority of a democratic society."