Hillary Clinton has clinched the Democratic nomination for US president after reaching the required number of delegates, an AP tally suggests.
She will become the first female nominee for a major US political party.
But rival Bernie Sanders said Mrs Clinton had not won as she was dependent on superdelegates who could not vote until July's party convention.
Mrs Clinton reached the threshold with a big win in Puerto Rico and a burst of last-minute support from superdelegates, AP said late on Monday night.
Superdelegates are party insiders who can pledge their support for a candidate ahead of the convention but do not formally vote for them until the convention itself.
Read more: Hillary Clinton 'secures Democratic nomination' - AP - BBC News