Organisers of a far-right rally set for Saturday in San Francisco said they have cancelled the event over fears of a "huge riot".

Joey Gibson, leader of the group Patriot Prayer, said Friday that members had been in contact with police and decided tomorrow's event "seems like a set up".

"It doesn't look safe, a lot of lives are going to be in danger," he said in a Facebook video. "In our opinion, it seems it would have been a huge riot."

He blamed local politicians and the media for drumming up fears by "saying that we are white supremacists".

The US remains on edge after a white supremacist rammed through crowds of anti-racist protesters, killing at least one, at a rally in Charlottesville on August 12.

Earlier in a written statement, Nancy Pelosi, the US House Democratic leader, had condemned the planned Patriot Prayer gathering as a dangerous "white supremacist rally".

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Organisers said they would instead hold a press conference at the liberal city's Alamo Square Park at 2:00pm (21:00 GMT).

However, San Francisco's mayor said he did not trust the group.

Mayor Ed Lee said that despite organisers saying it was called off, they have not cancelled the event in writing so the city was proceeding as though it was still happening.

"We don't trust this group. I never have from the beginning," Lee said, as he urged people not to show up at the news conference the group plans to hold instead of the rally.

No permits had been requested or granted for the press conference location.

"Public safety is always our top priority. We are prepared for contingencies and spontaneous events," Lee said.

A "No to Marxism in America" rally in neighbouring Berkeley planned for Sunday was also up in the air, with organiser Amber Cummings asking people not to attend.

Police are on watch in both locales, with counterprotests still possible.

Anti-racists had planned on demonstrating against the Patriot Prayer group in the same location, Crissy Fields. Authorities had feared a clash could erupt between the two groups.