U.S. President Barack Obama promised Saturday to do "whatever it takes" to maintain growth in the U.S. economy as he announced a summit with business leaders dedicated to job creation at home.

"This year, I'm going to keep doing whatever it takes to move this economy forward and to make sure that middle class families regain the security they've lost over the past decade," Obama said in his weekly radio and Internet address.

Republican presidential candidates in a debate Friday flubbed answers, made racist, homophobic outbursts and generally embarrassed themselves -- well, at least in a Yahoo! online spoof.

Even in the wild and unpredictable Republican primary season, things haven't got quite as wild as in the mock debate presented by Yahoo! and the Funny or Die comedy channel.

U.S. Vice President Joe Biden called Turkish Prime Minister Recep Tayyip Erdogan to discuss regional security, including Iraq's political crisis, the White House said Thursday.

The call followed up on Biden's visit to Turkey in December, and included an undertaking to work to support the rule of law and encourage democracy in the region, the White House said in a statement.

U.S. President Barack Obama vowed Thursday the U.S. military would maintain its "superiority" and bolster its presence in Asia despite planned cuts to the defense budget.

"So, yes, our military will be leaner, but the world must know -- the United States is going to maintain our military superiority with armed forces that are agile, flexible and ready for the full range of contingencies and threats," Obama told reporters at the Pentagon.

China said Wednesday it opposed "unilateral" sanctions against Iran, after U.S. President Barack Obama signed into law new measures targeting the Islamic republic's central bank.

Washington's move came after the United States, Britain and Canada said in November they were slapping additional sanctions on Iran, citing evidence that Tehran is pursuing nuclear weapons.

Texas Governor Rick Perry said Tuesday he would reassess his White House bid after suffering a heavy defeat in Iowa's first vote of the 2012 U.S. presidential elections.

"With the voters' decision tonight in Iowa, I have decided to return to Texas, assess the results of tonight's caucus, determine whether there is a path forward for myself in this race," Perry told supporters.

Iran successfully test fired a medium-range surface-to-air missile on Sunday during navy war games taking place near the strategic Strait of Hormuz, a spokesman for the maneuvers said, according to the official IRNA news agency.

"This medium-range surface-to-air missile is equipped with the latest technology to combat radar-evading targets and intelligent systems which try to disrupt missile navigation," Commodore Mahmoud Mousavi was quoted as saying.

Top negotiator Saeed Jalili said Iran was ready to rejoin EU-led talks with major powers on assuaging Western concerns over its nuclear program even as tensions with the United States soared in the Gulf.

"We will give a resounding and many-pronged response to any threat against the Islamic Republic of Iran," Jalili told Iranian diplomats gathered in Tehran in comments reported on Saturday.

The United States is considering Yemeni President Ali Abdullah Saleh's request to visit, but would only grant him entry for "legitimate" medical treatment, a senior U.S. official said Monday.

Officials also said President Barack Obama's top anti-terror advisor John Brennan called Yemeni Vice President Abdrabuh Mansur Hadi on Sunday to urge "maximum restraint" after forces backing Saleh killed 13 demonstrators.

Republican leaders bowed to intense pressure Friday and voted to extend a payroll tax holiday for 160 million Americans, handing victory to President Barack Obama after a tense showdown.

The deal, which finally sailed unopposed through the Senate and the House of Representatives two days before Christmas, allows Obama to end the year on a triumphant note after being thwarted by Republicans for months.