President Obama spoke about the Ukraine crisis Friday afternoon, saying, "The United States will stand with the international community in affirming that there will be costs for any military intervention in Ukraine."
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In this image from TV, President Obama shakes hands with Cuban President Raul Castro at the memorial service for former South African President Nelson Mandela in Johannesburg on Tuesday.
Then-Secretary of State Hillary Clinton and Vice President Biden at a White House event in October 2011. A new book says President Obama's aides were then studying whether to replace Biden with the former first lady on the 2012 ticket.
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Children release 95 balloons to mark Nelson Mandela's upcoming birthday outside the Mediclinic Heart Hospital where Mandela is being treated for a recurring lung infection in Pretoria, South Africa.
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Former President George W. Bush and his successor, President Obama, at the April 25 dedication of Bush's library on the campus of Southern Methodist University in Dallas.
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President Obama walks across the tarmac to greet well-wishers on Sunday upon his arrival in Atlanta, Ga., where he will attend the commencement at Morehouse College.
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