It follows a number of incidents where members have posted inappropriate tweets.
William Henwood, a Ukip candidate in Enfield, tweeted about Lenny Henry saying he should emigrate to a “black country” and does “not have to live with whites”.
Ukip member Andre Lampitt, who starred in one of the party’s promotional videos, was suspended after he called Ed Miliband “not British”, said Africans should “kill themselves off”, Islam is “evil” and Nigerians are “bad people”,
In the latest scandal, Kerry Smith, a Ukip parliamentary candidate, was recorded making remarks about homosexuals and Chinese people.
Nigel Farage described him as a “rough diamond”.
Ukip’s national executive council has threatened to suspend members who embarrass the party under new rules it has introduced governing their use of social media sites.
According to the Observer, the new rules state “party members shall refrain from using the Ukip logo in terms of their online postings, including avatars, unless they have express written consent to do so from the party leader, the party chairman, the party secretary, the general secretary, the party director, the regional chairman or regional organiser for their region.”
Writing in the Ukip members’ magazine, Mr Crowther said: “The NEC has adopted a new set of rules for online communication to fill a notable hole in our code of discipline … My advice: just don’t. Remember life before you could delight the whole world with your every passing thought? It wasn’t so bad, was it? I have no Facebook page, Twitter account or Instagram thingy. It’s lovely.”
A spokesman for Ukip claimed the move is also to prevent imposters using the logo by setting up fake accounts.