Hillary Clinton has reached the number of delegates needed to clinch the Democratic nomination for the US presidential race, according to the Associated Press.

According to the news agency's count of secured pledges from delegates won in primaries and caucuses, and a survey of party insiders known as superdelegates, Clinton has the overall support of the required 2,383 delegates.

The win will make Ms Clinton the first woman to heard a major US party ticket.

The reports came just moments ahead of a Clinton rally in California and when Ms Clinton took to the stage she appears to acknowledge the situation, telling the crowd that "according to the news we are on the brink of a historic - historic, unprecedented moment".

But she said there was "still work to do".

The development follows the former secretary of state's win in Puerto Rico over the weekend a burst of last minute support from superdelegates, according to the Associated Press.

Superdelegates are party officials. They are not due to formally cast their votes until the Democratic National Convention in Philadelphia in July.

Bernie Sanders, Ms Clinton's rival for the nomination, said he will work to change the minds of superdelegates ahead of the convention.

A statement from his campaign said: