Seeking to quell a growing scandal, President Barack Obama said Monday it would be "outrageous" if U.S. tax authorities targeted conservative groups fiercely opposed to his White House.

As he battled growing political woes, Obama also denied his White House had engaged in a cover-up to downplay the impact to his re-election campaign of the attack on the U.S. mission in Benghazi last year, which killed four Americans.

The United States and Britain on Monday pledged to forge ahead with diplomatic efforts to end the civil war in Syria, saying they had found common ground with Russia on how to proceed.

U.S. President Barack Obama and British Prime Minister David Cameron vowed to increase pressure on the regime of Syria's President Bashar Assad, and insisted that he could not be part of a democratic transition.

U.S. President Barack Obama will visit Berlin next month for talks with German Chancellor Angela Merkel, a German government spokesman said Friday.

Deputy spokesman Georg Streiter told a regular news briefing that Obama would stop in Berlin June 18-19, after a G8 summit in Northern Ireland.

U.S. President Barack Obama on Thursday launched yet another effort to pressure Congress to act on his plans to invest in education and innovation to create a new generation of high-paying jobs.

Obama flew to Texas to highlight school and industry programs seen as a model method of firming up sluggish growth and taking aim at unemployment, which remains at 7.5 percent more than four years into his presidency.

Former U.S. secretary of state Hillary Clinton hailed China's President Xi Jinping on Wednesday as "pragmatic," saying he was more of a politician than his predecessor.

In an address to a think tank in Los Angeles she said Xi, who took office last November, should ensure that there is "no daylight" between the ruling Communist Party and China's vast military.

U.S. President Barack Obama will meet British Prime Minister David Cameron at the White House on Monday to discuss Syria and the G8 summit next month in Northern Ireland, officials said.

"The prime minister's visit underscores the special relationship between the United States and the United Kingdom that has been crucial in advancing our shared security and prosperity," a White House statement said.

U.S. President Barack Obama said Tuesday he had both a moral and a national security obligation to stop the slaughter in Syria, but warned he could not just act on a "hope and a prayer."

Obama defended his government's actions in sending large quantities of humanitarian aid to Syrian refugees, providing non-lethal help to rebels and isolating President Bashar Assad in the international community.

U.S. President Barack Obama and South Korea's new leader on Tuesday plotted the next moves on North Korea amid signs that the bellicose regime has stepped back from the brink as it faces growing pressure.

On her first foreign trip since her election as Northeast Asia's first woman leader, President Park Geun-Hye is seeking both a show of unity and to keep momentum in South Korea's drive to build an outsized role in world affairs.

U.S. President Barack Obama turned the spotlight on economic ties with Latin America on Saturday as he wrapped up a three-day trip to a region roiled by drug violence.

Obama sought to shift the narrative away from the drug war during visits to Mexico and Costa Rica this week, praising trade as a path to fighting poverty and creating jobs that turn young people away from a life of crime.

President Barack Obama came close to ruling out deploying U.S. troops to Syria, saying he did not foresee a scenario in which that would be beneficial to the United States or Syria.

"As a general rule, I don't rule things out as commander-in-chief because circumstances change and you want to make sure that I always have the full power of the United States at our disposal to meet American national security interests," said Obama, speaking during a visit to Costa Rica late Friday.