U.S. President Barack Obama offered "warm wishes" on behalf of the American people to newly elected Pope Francis I on Wednesday, hailing the Argentine as "the first pope from the Americas."

"As a champion of the poor and the most vulnerable among us, he carries forth the message of love and compassion that has inspired the world for more than two thousand years, that in each other we see the face of God," he said.

President Barack Obama entered the fray Wednesday on cyber attacks from China, saying some intrusions affecting U.S. firms and infrastructure were "state sponsored."

The comments appeared to step up the rhetoric against China following similar remarks from other members of the U.S. administration.

The United States said it condemned any use of phosphorus as a crowd control measure after an official Myanmar report Tuesday found the toxic agent had been used to end a rally at a copper mine.

Dozens of people, including monks, were injured in the November clampdown, many suffering burns from the white phosphorus, according to a parliamentary report led by opposition icon Aung San Suu Kyi.

The United States on Tuesday said it took "note" of an overwhelming vote by Falkland Islanders to remain a British territory, but refused once again to take sides in the dispute with Argentina.

"The residents have clearly expressed their preference for a continued relationship with the United Kingdom," State Department spokeswoman Victoria Nuland said.

France, Russia and the United States are trying to draw up a list of Syrian officials with whom the opposition can negotiate, French Foreign Minister Laurent Fabius said on Tuesday.

"We worked together on an idea... of a list of Syrian officials who would be acceptable to Syria's opposition National Coalition," he told the foreign affairs committee of the National Assembly.

U.S. spy chief James Clapper on Tuesday warned that America faced a growing threat of a crippling cyber attack and voiced alarm over North Korea's recent "belligerent" rhetoric.

In an annual assessment of global threats, the national intelligence director warned of an array of dangers around the world, from Pyongyang's bellicose stance to food shortages driven by extreme weather, but placed a particular emphasis on the threat posed by potential cyber attacks.

The United States Monday condemned what it called a "terrorist" assault on Syrian regime forces who came under fire after crossing into Iraq last week in an attack claimed by an al-Qaida group.

"Any kind of attack like this, any kind of terrorism like this is something that we should condemn," State Department spokeswoman Victoria Nuland said.

The White House on Monday strongly rejected allegations from Afghan President Hamid Karzai that the United States was colluding with the Taliban to justify the presence of U.S. troops in the country.

"That's categorically false, and nobody believes it," White House spokesman Jay Carney said when asked about Karzai's remarks.

The United States has expelled two Venezuelan diplomats in a tit-for-tat move after Caracas ordered two U.S. Air Force officers out of the country, the State Department said Monday.

Embassy second secretary Orlando Jose Montanez and consular official Victor Camacaro, who worked in New York, were each declared "persona non grata" by the United States on Saturday, department spokeswoman Victoria Nuland said.

South Korea and the United States launched joint drills Monday involving thousands of troops, defying North Korea's apocalyptic threat to repudiate the 60-year-old Korean War armistice in retaliation.

The start of the two-week "Key Resolve" exercise follows a week of escalating tensions on the Korean peninsula, with North Korea also threatening nuclear war over U.N. sanctions adopted after its third atomic test last month.