Facebook has banned the far-right political group Britain First for breaking rules that prohibit hate speech on the social media platform.

The organization's official Facebook page has been removed, along with those of Britain First leaders Paul Golding and Jayda Fransen. Facebook (FB) said they had "repeatedly posted content designed to incite animosity and hatred against minority groups."

"There are times ... when legitimate political speech crosses the line and becomes hate speech designed to stir up hatred against groups in our society," Facebook said in a statement.

Britain First gained international attention last year when President Donald Trump retweeted three inflammatory videos posted by Fransen on Twitter, setting off a political firestorm that strained relations between London and Washington.

The group's accounts were later suspended by Twitter (TWTR).

Political leaders and big advertisers are increasing the pressure on social media companies do more to remove objectionable and illegal material from their platforms.

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Facebook CEO Mark Zuckerberg has said his personal challenge for 2018 is to prevent Facebook from being misused in ways that potentially do harm to its billions of users and to society at large.

"We are an open platform for all ideas and political speech goes to the heart of free expression," the company said on Wednesday. "But political views can and should be expressed without hate."

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Britain First describes itself as "a patriotic resistance and 'frontline' for our long suffering people" that will "restore Christianity as the bedrock" of national life and put British workers first.

But it's on the extreme fringe of political life in the UK.

It has no elected representatives at any level of British politics and has been "deregistered" as a political party by the UK Electoral Commission. Its occasional protests rarely attract crowds of more than a few dozen.

-- CNN's Alanna Petroff contributed reporting.