Hillary Clinton has captured enough delegates for her party's nomination, according to an AP count. She goes into the last big round of primaries as the presumptive Democratic nominee for president.
Clinton had received enough commitments from delegates by Monday to become the Democratic Party's presumptive presidential nominee, the Associated Press reported.
AP said the count of delegates won in primaries and caucuses, as well as a survey of party insiders known as superdelegates, showed that Clinton had the overall support of the required 2,383 delegates.
The former secretary of state was reported to have crossed the crucial threshold with a decisive weekend win in Puerto Rico. As a result, the agency said, Clinton had 1,812 pledged delegates and could count on the support of 571 superdelegates.
Clinton welcomed the news in a rally at Long Beach, California, but urged supporters to concentrate on forthcoming votes in six US states.
"According to the news we are on the brink of an historic, unprecedented moment. But we still have work to do, don't we? We have six elections tomorrow and we're going to fight hard for every single vote, especially here in Calilfornia," Clinton said on Monday.
Sanders' team blames media
The campaign team behind Clinton's nomination opponent, Bernie Sanders, said it was wrong for the media to call Clinton's nomination.
"It is unfortunate that the media, in a rush to judgement, are ignoring the Democratic National Committee's clear statement that it is wrong to count the votes of superdelegates before they actually vote at the convention this summer," said Sanders' spokesman Michael Briggs.
Clinton "does not have and will not have the requisite number of pledged delegates to secure the nomination," Briggs said, adding that Sanders would seek to "convince those superdelegates that Bernie is by far the strongest candidate against Donald Trump."
As the presumptive nominee, the former first lady would formally accept her party's nomination in July at the Democratic National Convention in Philadelphia.
Securing a historic first
The nomination would make Clinton the first woman to run at the top of the ticket for a major US political party. It would also see Clinton take on divisive billionaire businessman Donald Trump in the November elections, with the Oval Office as the ultimate prize.
Clinton had vowed earlier on Monday that she would "take the fight to Donald Trump and defeat him in November."
Clinton leaves Sanders trailing by more than 3 million cast votes; 291 pledged delegates and 523 superdelegates - a wider margin of victory than President Barack Obama had when he clinched the nomination in 2008.