A senior figure in the campaign for UK exit from the EU has urged the Home Office to bar French far right leader Marine Le Pen from visiting Britain.
Vote Leave co-chairman Gisela Stuart said Ms Le Pen held "divisive and inflammatory" views and her visit would not be "conducive to the public good".
The president of the French National Front, who backs Brexit, is expected to travel to the UK in the next few weeks.
The Home Secretary told the BBC she does not comment on individual cases.
Ms Le Pen has said she intends to speak in favour of Britain leaving the EU and wants France, like the UK, to hold a referendum on leaving.
In a letter to Home Secretary Theresa May sent on Friday, Ms Stuart said the National Front leader "has previously made many divisive and inflammatory comments, including comparing Muslims praying in the street to the Nazi occupation of France".
"Accordingly, I urge you to exercise your powers under immigration legislation to refuse her admission into the country if and when she attempts to visit the UK."
Ms Stuart said there was "ample precedent" to refuse Ms Le Pen entry, based on Home Office decisions to bar others in recent years.
According to figures published in 2014, Mrs May has banned more than 217 people since 2010, including 84 hate preachers, 61 people on grounds of national security and 72 because they were deemed "not conducive to the public good".
Mrs May told the BBC's Andrew Marr Show she "never talks about individual decisions" on this. She has previously said banning decisions are taken "on the basis of the evidence at the time".
Ms Le Pen has spoken in favour of French withdrawal from the EU and eurozone, which she says would allow France to restrict immigration, impose customs duties on imports, nationalise some big businesses and re-instate the franc.
She denies accusations that her party is racist and anti-Semitic.
Correspondents say the National Front has been following the EU debate in the UK closely and hopes a vote for Brexit would lift its political fortunes in France, which holds presidential elections next year.
Party spokesman Alain Vizier said on Wednesday: "Marine Le Pen is bound to go [to the UK]. The date has not been set, it would be at the end of May or early June.
"She would go for a day or half a day," he said, adding only that "she will campaign for Brexit".
Earlier in the week, Ms Le Pen said in a French radio interview: "Every nation in Europe has the right to be asked that question - do you want to stay in this structure... or not.
"The first step was organised by Mr [David] Cameron."
The UK's in/out referendum on the EU will be held on 23 June.