'I've known Trump's a bully for a long time': NYC Mayor Bill de Blasio focused on his history battling Trump as he announced a run for president

• Bill de Blasio, mayor of New York City, has announced his run for the Democratic presidential nomination.
• A video released on Thursday references his history with President Donald Trump, who he describes as a "bully" and said: "I've beaten him before and I will do it again."
• He also focused on the idea of "working people first" and outlined progressive policies he introduced in New York.
• He is the 23rd Democrat to enter the race.

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New York City Mayor Bill de Blasio announced his 2020 presidential bid, focusing on his history of disputes with President Donald Trump.

In a video released on Thursday announcing his run for the Democratic nomination, De Blasio referenced his history with Trump, describing him as a "bully."

"I've known Trump's a bully for a long time ... and I know how to take him on," he said.

He concluded that the president '"must be stopped," and that he is that man to do it because "I've beaten him before and I will do it again."

In the video, he outlined how he sent lawyers to the US-Mexico border to help families affected by the Trump administration's family separation policy, sued Donald Trump over the cutting off of security funding, and opposed Trump's withdrawal of the US from the Paris agreement on climate change.

De Blasio centered his video on the theme of "working people first," outlining NYC's increase in the minimum wage to $15 an hour, the introduction of paid sick leave, and his belief that healthcare is "a human right."

De Blasio has been meeting with voters in Iowa and New Hampshire, and is now the 23rd person to declare as a Democratic candidate.