A planned protest outside Twitter's San Francisco headquarters against the social media platform's ban of Donald Trump fizzled out Monday when just a handful of the US president's supporters turned up.

Messages posted this weekend on popular far-right forum TheDonald.win had called on pro-Trump activists to assemble outside the tech giant's offices, which are largely deserted as staff work from home due to the pandemic.

One user even urged participants to bring zip ties to "citizen arrest violent agitators," the San Francisco Chronicle reported.

Police deployed dozens of officers and constructed security barriers, but only a few protesters and counter-protesters arrived.

"I don't like being censored. And I feel conservative voices are being censored," one protester told the local Fox television station KTVU.

Police deployed dozens of officers and constructed security barriers outside Twitter's San Francisco headquarters, but only a few protesters and counter-protesters arrived
Police deployed dozens of officers and constructed security barriers outside Twitter's San Francisco headquarters, but only a few protesters and counter-protesters arrived AFP / JOSH EDELSON

Kenneth Lundgreen, 71, told the Chronicle he wanted to "act as a counter balance" in case a crowd like the one that stormed the US Capitol in Washington, DC last week arrived.

Shortly after that unrest, Twitter imposed a permanent ban on Trump's account -- which had 88 million subscribers -- prompted by multiple violations of its rules and the risk of "further incitement of violence."

Trump accused the company of conspiring with the "Radical Left," while some international leaders including German Chancellor Angela Merkel have called the ban "problematic."

Other platforms including Facebook and Snapchat also have suspended Trump.

US Democrats have launched the process of impeaching Trump for a historic second time for "incitement of insurrection" over the attack on the Capitol, in which five people died.