Nikki Sinclaire announced her refusal to continue in the bloc on her website
A Euro MP has been expelled from the UK Independence Party after refusing to be part of a multi-national group it has joined in the European Parliament.
Nikki Sinclaire had said some of UKIP's allies in Europe of Freedom and Democracy (EFD) had "extreme views".
The West Midlands Euro MP has refused to sit with her own party members in European Parliament meetings for weeks.
UKIP said her plans to stand also as a candidate for the party in the general election may not go ahead.
'May not stand'
Ms Sinclaire has refused to sit with her own party in European Parliament meetings since mid-January, citing the breakdown of her relationship with UKIP leader in Europe Nigel Farage and the "extreme views" of some of UKIP's political allies.
She insisted she was not quitting the party, but UKIP's National Executive Committee has removed the whip, reducing UKIP's team of MEPs to 12.
A UKIP statement on Thursday said: "Nikki Sinclaire says that her political views are incompatible with those of some members of the EFD Group in the European parliament, of which the UKIP MEPs form part.
"So she has been sitting as an unattached MEP since 18 January 2010.
"She has also proved unable to collaborate adequately with the voluntary party in the UK, particularly with the regional committee in the West Midlands.
"The national executive committee has therefore removed the whip; Nikki Sinclaire may no longer describe herself as a UKIP MEP, and she may not stand as a UKIP candidate in the forthcoming general election."
The EFD group was formed in Strasbourg after last summer's euro-elections, made up of 32 right-wing MEPs from nine national political parties.
Ms Sinclaire announced her refusal to continue in the bloc on her website, attacking a "variety of extremist views" of other EFD members, including "anti-Semitism, violence and the espousal of a single European policy on immigration".
Ms Sinclaire claimed Mr Farage had admitted to her "that he wished I had not been elected" and added: "I have found this personal animosity difficult to work with."
Mr Farage remains an MEP but has stepped down as UKIP national leader to concentrate on fighting John Bercow's Buckingham seat in the forthcoming general election.
Ms Sinclaire had expected to stay on in the party, insisting she had the support of new UKIP national leader Lord Pearson, who had assured of support "both now and in the future in my continued work for UKIP".