Facebook said on Wednesday it banned Britain First from its platform for breaking rules against inciting hatred, blacklisting a far-right group brought to global attention when U.S. President Donald Trump retweeted its anti-Islamic posts.

Facebook said it had taken down Britain First's Facebook page and those of its leaders, Paul Golding and Jayda Fransen, for repeatedly violating rules designed to stop the incitement of hatred against minority groups.

A fringe party, British First shot to the fore last November when Trump sparked outrage in Britain and a sharp rebuke from Prime Minister Theresa May for retweeting British far-right anti-Islam videos.

May condemned his decision as "wrong", prompting a diplomatic spat with Washington, although Trump later apologized, saying he did not know the group's background.

In a blog post, Facebook said: "Content posted on the Britain First Facebook page and the pages of party leaders Paul Golding and Jayda Fransen has repeatedly broken our community standards.

"We recently gave the administrators of the pages a written final warning, and they have continued to post content that violates our community standards.

"As a result, in accordance with our policies, we have now removed the official Britain First Facebook page and the pages of the two leaders with immediate effect.

"We do not do this lightly, but they have repeatedly posted content designed to incite animosity and hatred against minority groups, which disqualifies the pages from our service."

The social media giant said it was an open platform for all ideas, and "we are careful not to remove posts or pages just because some people don't like them".

But it warned that "there are times though when legitimate political speech crosses the line and becomes hate speech".

The removal of the Britain First pages comes as Facebook and other internet firms like Twitter and Google are under growing pressure to police their networks, refereeing content to prevent extremist groups spreading their messages and recruiting online.

May has joined forces with the leaders of France and Italy to urge social media companies to do more to remove extremist content. She said on Wednesday that she welcomed the announcement by Facebook.

"I hope other companies will follow," she told British lawmakers.