Obama praises 'valiant' Clinton

Democratic hopeful Barack Obama has paid tribute to Hillary Clinton for her "valiant campaign" to become the party nominee for US president.
He said his former rival had "shattered barriers on behalf of my daughters and women everywhere".
The praise came after Mrs Clinton formally abandoned her bid for the nomination at a rally in Washington.
She said Mr Obama had proved his "grace and grit", and she urged her supporters to put their energy into electing him.
Mr Obama is expected to face the Republican presumptive nominee, John McCain, in November's presidential election.
In a statement, Mr Obama said he was "thrilled" to have Mrs Clinton's endorsement.

Senator Clinton gives Barack Obama her backing
He credited her with reaching out to many American voters and making him a stronger candidate.
"She inspired millions with her strength, courage and unyielding commitment to the cause of working Americans."
Mr Obama also said Mrs Clinton's presence on the American political scene would continue.
"No one knows better than Senator Clinton how desperately America and the American people need change, and I know she will continue to be in the forefront of that battle this fall and for years to come."
His campaign website asked supporters to send a message of thank you to the Clinton campaign.
Angry supporters
Earlier, Mrs Clinton formally suspended her 16-month-long campaign with a speech at the National Building Museum in Washington.
She opened by saying: "This isn't exactly the party I planned but I sure like the company."
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Mrs Clinton thanked the "18 million of you from all walks of life" who voted for her and threw her support behind Mr Obama.
Although she had not succeeded, she said there were now "18 million cracks in the glass ceiling" preventing a woman from winning the White House.
Referring to her formal rival, she said: "I've had a front-row seat to his candidacy and I have seen his strength and determination, his grace and his grit."
The BBC's Kevin Connolly at the venue says there was an angry feeling among many of her supporters that Mr Obama only won because the complex rules of the Democratic Party process suited his campaign.