New York Mayor Bill de Blasio drops out of 2020 presidential race

New York Mayor Bill de Blasio, who vowed to take on "bully" President Donald Trump, officially dropped out of the 2020 presidential race on Friday, ending his campaign after struggling to gain traction in the runoff.

"I feel like I contributed all I can to this primary election and it's clearly not my time," he said during an appearance on MSNBC's "Morning Joe".

"So, I'm going to end my presidential campaign, continue my work as mayor of New York City and I'm going to keep speaking up for working people," he added.

The Democrat entered the presidential race in May. The mayor qualified for the first two rounds of Democratic presidential debates but failed to make the cut for the others, Fox News reported.

According to the Real Clear Politics average, de Blasio was polling at less than 1 per cent nationally. The Democrat had recently hinted he would end his long-shot bid if he did not qualify for the October debates.

Shortly after the announcement, Trump mocked de Blasio over his departure from the race on Twitter.

"Oh no, really big political news, perhaps the biggest story in years! Part time Mayor of New York City, @BilldeBlasio, who was polling at a solid ZERO but had tremendous room for growth, has shocking dropped out of the Presidential race. NYC is devastated, he's coming home!" the president wrote.

De Blasio has regularly criticised Trump on immigration, policing and climate change.

He also held an event at the base of Trump Tower in May calling on all the president's businesses to cut their emissions in line with New York's Green New Deal legislation, a package of environmental laws.

This prompted a Twitter battle with Trump's son, Eric, who called the rally "simply childish".