Twitter chief executive Jack Dorsey has issued a series of tweets to say banning US President Donald Trump from the social media platform after last week’s violence at the Capitol was the “right decision,” but worries about setting a dangerous precedent.

“Having to take these actions fragment the public conversation,” Mr Dorsey wrote in his first statement on the matter.

“They divide us. They limit the potential for clarification, redemption, and learning. And sets a precedent I feel is dangerous: the power an individual or corporation has over a part of the global public conversation.”

Tweet from @jack

San Francisco-based Twitter last week removed Mr Trump’s account, which had 88 million followers, citing the risk of further violence following the storming of the Capitol by supporters of the President.

The ban drew criticism from some Republicans who said it quelled the president’s right to free speech. German Chancellor Angela Merkel also warned through a spokesman that legislators, not private companies, should decide on potential curbs to free expression.

In his Twitter thread, Mr Dorsey said while he took no pride in the ban, “offline harm as a result of online speech is demonstrably real, and what drives our policy and enforcement above all”.

Even so, he added, “While there are clear and obvious exceptions, I feel a ban is a failure of ours ultimately to promote healthy conversation.”

Banning the @RealDonaldTrump Twitter account had “real and significant ramifications,” Mr Dorsey wrote, noting how the widespread suspension of the President by many platforms challenged the notion that if people didn’t like Twitter’s rules, they could simply go somewhere else.

Twitter has introduced a series of measures in the past year such as labels, warnings and distribution restrictions to reduce the need for decisions about removing content entirely from the service.

Mr Dorsey has said he believes those measures can promote more fruitful, or “healthy”, conversations online and lessen the impact of bad behaviour.

The Twitter CEO said bans by social media companies on Mr Trump after last week’s violence were emboldened by each other’s actions even though they were not co-ordinated. But in the long term, the precedent set “will be destructive to the noble purpose and ideals of the open internet”.

Supporters of Mr Trump who has repeatedly made baseless claims challenging Democrat Joe Biden’s victory in the November election, stormed the US Capitol on Wednesday, trying to halt the certification by Congress of Mr Biden’s Electoral College win.

On Wednesday, Mr Trump became the first president in US history to be impeached twice.

All of the major social media platforms – Facebook, Google’s YouTube, Snap – have now banned the president, too. Snap said late Wednesday (US time) that it would make its ban permanent.

-with AAP