Hillary Clinton has told her supporters to unite behind Barack Obama as she suspended her campaign to become the Democratic nominee for US president.
She was grateful to "all who poured [their] hearts into this campaign" and urged them to "take our energy, our passion" and help elect Barack Obama.
Mr Obama praised Mrs Clinton's "valiant campaign" and was "thrilled and honoured" to secure her support.
He will face the Republican presumptive nominee, John McCain, in November.
'Glass ceiling'
Mrs Clinton was given a huge ovation for her speech at the National Building Museum in Washington.
The highs and lows of Hillary Clinton's primary campaign
She opened by saying: "This isn't exactly the party I planned but I sure like the company."
Mrs Clinton thanked the "18 million of you from all walks of life" who voted for her.
She urged supporters to now ensure all their energy and passion was directed towards getting Mr Obama elected.
"Today as I suspend my campaign, I congratulate him on the victory he has won and the extraordinary campaign he has won," Mrs Clinton said.
"I endorse him and throw my full support behind him and I ask of you to join me in working as hard for Barack Obama as you have for me."
In response, Mr Obama said Mrs Clinton had "shattered barriers on behalf of my daughters and women everywhere, who now know that there are no limits to their dreams".
A hard-faced woman - an aggressive woman - is not something America is culturally attuned to liking
Much of Mrs Clinton's speech focused on her fight to be the first woman president of the US.
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.
She said: "Let us resolve and work toward achieving a very simple proposition: there are no acceptable limits, and there are no acceptable prejudices in the 21st Century in our country."
She added: "Children today will grow up taking for granted that an African-American or a woman can, yes, become the president of the United States."
Mrs Clinton told her supporters to: "Aim high, work hard and care deeply about what you believe in."
Key meeting
The BBC's Kevin Connolly, at the National Building Museum, says Mrs Clinton's supporters had queued there for six hours in gruelling humidity to hear her.
Aim high, work hard and care deeply about what you believe in Hillary Clinton
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In quotes: Clinton concedes
He added: "She inspired millions with her strength, courage and unyielding commitment to the cause of working Americans."
He 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.
Mr Obama won enough delegates to effectively secure the nomination after the final primaries on Tuesday.
Intense speculation remains about who Mr Obama will choose as his running mate.
Mrs Clinton met Mr Obama on Thursday but little has been made public of the meeting.
Mrs Clinton has distanced herself from reports that she was hoping to be on the November ticket with Mr Obama.
HAVE YOUR SAY I voted for Clinton and now I'll be voting for McCain. Obama's campaign has been more wishy-washy than John Kerry's ever was
Marshall Craig, Dallas, Texas
Send us your commentsA statement from Mrs Clinton's campaign on Thursday said she was "not seeking the vice-presidency".
It added: "The choice here is Senator Obama's and his alone."
Mr Obama has announced a team to help him make his selection but has said he will not be rushed.
In his statement on Saturday, Mr Obama said Mrs Clinton would "continue to be in the forefront of the battle" in the autumn.
The BBC's Kim Ghattas in Washington says that although the decision on the running mate is Mr Obama's, Mrs Clinton would also face a tough choice if offered it.
If she does not take it, our correspondent says, it may look as if she is not doing enough for Mr Obama, but if she accepts and Mr Obama loses she may be blamed for the defeat.
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HRC hasn't been my candidate of choice, and I've been pretty upset with some of her tactics during this campaign, but kudos to her for this speech! I appreciate it as a Democrat AND a woman. Thank you, Hillary; you've restored my respect for you and put the country's good ahead of your own ambitions.
henryGal 3 years ago 7
She is an amazing and strong woman, not only intelligent but very well informed. I hope next election she will run again and hopefully she will get the chance of all the good she is able to do for our country. Hillary I know we have asked a lot from you but please run again in four years.
cazzovoglio 3 years ago 3